diff --git a/SVSim.Database/Models/Config/ColosseumRoundsConfig.cs b/SVSim.Database/Models/Config/ColosseumRoundsConfig.cs
index 922c3b82..c0744070 100644
--- a/SVSim.Database/Models/Config/ColosseumRoundsConfig.cs
+++ b/SVSim.Database/Models/Config/ColosseumRoundsConfig.cs
@@ -1,7 +1,10 @@
+using SVSim.Database.Enums;
+
 namespace SVSim.Database.Models.Config;
 
 /// <summary>
-/// The 3-round bracket schedule for an active Colosseum season. Empty <see cref="Rounds"/>
+/// The 3-round bracket schedule for an active Colosseum season — and the per-round
+/// reward bundles paid out by <c>/finish</c> + <c>/retire</c>. Empty <see cref="Rounds"/>
 /// is the default shipped state — lobby <c>/event_info</c> renders a benign payload with
 /// no rounds active. Collection default is in <see cref="ShippedDefaults"/> per
 /// feedback_config_defaults (property-initializer collection defaults silently empty out
@@ -12,9 +15,14 @@ public class ColosseumRoundsConfig
 {
     public List<RoundEntry> Rounds { get; set; } = new();
 
+    /// <summary>Champion-only reward bundle, paid alongside the final round's FinishRewards
+    /// when <c>ColosseumProgressionService</c> determines the viewer cleared the bracket.</summary>
+    public List<RewardEntry> ChampionRewards { get; set; } = new();
+
     public static ColosseumRoundsConfig ShippedDefaults() => new()
     {
         Rounds = new(),
+        ChampionRewards = new(),
     };
 
     public class RoundEntry
@@ -29,6 +37,15 @@ public class ColosseumRoundsConfig
         /// for late-joiners). The first entry is the canonical lookup used by
         /// <c>ColosseumProgressionService</c> for the v1 single-bracket case.</summary>
         public List<GroupEntry> Groups { get; set; } = new();
+
+        /// <summary>Paid by <c>/finish</c> when the viewer clears or otherwise ends this round
+        /// successfully. Empty = no bonus for this round.</summary>
+        public List<RewardEntry> FinishRewards { get; set; } = new();
+
+        /// <summary>Paid by <c>/retire</c> when the viewer abandons mid-round. Client ignores
+        /// these once <c>run.RoundId &gt;= FinalB</c>, but server still emits them per
+        /// retire.md (log completeness).</summary>
+        public List<RewardEntry> RetireRewards { get; set; } = new();
     }
 
     public class GroupEntry
@@ -44,4 +61,15 @@ public class ColosseumRoundsConfig
         /// <summary>Total bracket entries allotted to this group.</summary>
         public int EntryNumber { get; set; }
     }
+
+    public class RewardEntry
+    {
+        public UserGoodsType Type { get; set; }
+        public long DetailId { get; set; }
+        public int Count { get; set; }
+
+        /// <summary>Display name for the <c>rewards[]</c> receipt block. Defaults to empty;
+        /// client uses system-text lookups when blank.</summary>
+        public string Name { get; set; } = "";
+    }
 }
diff --git a/SVSim.EmulatedEntrypoint/Controllers/ArenaColosseumBattleController.cs b/SVSim.EmulatedEntrypoint/Controllers/ArenaColosseumBattleController.cs
new file mode 100644
index 00000000..12762dc4
--- /dev/null
+++ b/SVSim.EmulatedEntrypoint/Controllers/ArenaColosseumBattleController.cs
@@ -0,0 +1,175 @@
+using System.Text.Json;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using SVSim.BattleNode.Bridge;
+using SVSim.Database.Repositories.Viewer;
+using SVSim.EmulatedEntrypoint.Constants;
+using SVSim.EmulatedEntrypoint.Matching;
+using SVSim.EmulatedEntrypoint.Models.Dtos.ArenaColosseum;
+using SVSim.EmulatedEntrypoint.Security;
+using SVSim.EmulatedEntrypoint.Security.SteamSessionAuthentication;
+using SVSim.EmulatedEntrypoint.Services;
+using SVSim.EmulatedEntrypoint.Services.ArenaColosseum;
+
+namespace SVSim.EmulatedEntrypoint.Controllers;
+
+/// <summary>
+/// Per-match URLs for the Colosseum bracket — the dual <c>colosseum_battle/*</c> +
+/// <c>colosseum_rank_battle/*</c> route family. Does NOT extend <see cref="SVSimController"/>'s
+/// <c>[Route("[controller]")]</c> because we need explicit absolute routes for two prefixes
+/// off one controller (same pattern as <see cref="FreeBattleController"/>).
+/// <para>
+/// The URL is the bracket-phase signal per do-matching.md §"server-side bidirectional
+/// mapping"; <see cref="ViewerArenaColosseumRun.IsRankMatching"/> flips to true once the
+/// node has signalled <c>matching_state == 3008</c> on a prior <c>do_matching</c>.
+/// </para>
+/// </summary>
+[ApiController]
+[Authorize(AuthenticationSchemes = SteamAuthenticationConstants.SchemeName)]
+public sealed class ArenaColosseumBattleController : ControllerBase
+{
+    /// <summary>Per FinishTaskBase.IsEffectiveErrorCode — code 3502 ("battle already finished")
+    /// is tolerated as a non-error retry, parsed the same as 1.</summary>
+    private const int BattleAlreadyFinishedResultCode = 3502;
+
+    private readonly IMatchContextBuilder _ctxBuilder;
+    private readonly IMatchingResolver _resolver;
+    private readonly IArenaColosseumRunRepository _runs;
+    private readonly IColosseumProgressionService _progression;
+    private readonly ILogger<ArenaColosseumBattleController> _log;
+
+    public ArenaColosseumBattleController(
+        IMatchContextBuilder ctxBuilder,
+        IMatchingResolver resolver,
+        IArenaColosseumRunRepository runs,
+        IColosseumProgressionService progression,
+        ILogger<ArenaColosseumBattleController> log)
+    {
+        _ctxBuilder = ctxBuilder;
+        _resolver = resolver;
+        _runs = runs;
+        _progression = progression;
+        _log = log;
+    }
+
+    private bool TryGetViewerId(out long viewerId)
+    {
+        viewerId = 0;
+        var claim = User.Claims.FirstOrDefault(c => c.Type == ShadowverseClaimTypes.ViewerIdClaim)?.Value;
+        return claim is not null && long.TryParse(claim, out viewerId);
+    }
+
+    [HttpPost("/colosseum_battle/do_matching")]
+    public Task<IActionResult> DoMatchingPreRank(
+        [FromBody] ColosseumDoMatchingRequestDto req, CancellationToken ct)
+        => DoMatchingInternal(isRankUrl: false, req, ct);
+
+    [HttpPost("/colosseum_rank_battle/do_matching")]
+    public Task<IActionResult> DoMatchingPostRank(
+        [FromBody] ColosseumDoMatchingRequestDto req, CancellationToken ct)
+        => DoMatchingInternal(isRankUrl: true, req, ct);
+
+    [HttpPost("/colosseum_battle/finish")]
+    public Task<IActionResult> FinishPreRank(
+        [FromBody] ColosseumBattleFinishRequestDto req, CancellationToken ct)
+        => FinishInternal(isRankUrl: false, req, ct);
+
+    [HttpPost("/colosseum_rank_battle/finish")]
+    public Task<IActionResult> FinishPostRank(
+        [FromBody] ColosseumBattleFinishRequestDto req, CancellationToken ct)
+        => FinishInternal(isRankUrl: true, req, ct);
+
+    private async Task<IActionResult> DoMatchingInternal(
+        bool isRankUrl, ColosseumDoMatchingRequestDto req, CancellationToken ct)
+    {
+        if (!TryGetViewerId(out var vid)) return Unauthorized();
+
+        var run = await _runs.GetByViewerIdAsync(vid);
+        if (run is null)
+        {
+            return BadRequest(new { error = "arena_colosseum_no_active_run" });
+        }
+        if (isRankUrl != run.IsRankMatching)
+        {
+            return BadRequest(new
+            {
+                error = "colosseum_url_phase_mismatch",
+                is_rank_matching = run.IsRankMatching,
+                requested_rank_url = isRankUrl,
+            });
+        }
+
+        MatchContext ctx;
+        try
+        {
+            ctx = await _ctxBuilder.BuildForColosseumAsync(vid);
+        }
+        catch (InvalidOperationException ex)
+        {
+            _log.LogWarning(ex,
+                "Colosseum BuildForColosseumAsync failed for viewer {Vid}; returning 3001.", vid);
+            return Ok(new Models.Dtos.FreeBattle.DoMatchingResponseDto
+            {
+                MatchingState = 3001,
+                NodeServerUrl = "",
+            });
+        }
+
+        var mode = isRankUrl ? "colosseum_rank_battle" : "colosseum_battle";
+        var resolution = await _resolver.ResolveAsync(mode, new BattlePlayer(vid, ctx), ct);
+
+        // Promotion: server flips IsRankMatching once on the 3008 signal. Subsequent battle
+        // URLs must use the rank prefix. (Plan §"matching_state == 3008 is the promotion trigger".)
+        if (_progression.ShouldPromoteToRankMatching(run, resolution.MatchingState))
+        {
+            run.IsRankMatching = true;
+            await _runs.UpsertAsync(run);
+        }
+
+        return Ok(new Models.Dtos.FreeBattle.DoMatchingResponseDto
+        {
+            MatchingState = resolution.MatchingState,
+            BattleId = resolution.BattleId,
+            NodeServerUrl = resolution.NodeServerUrl,
+        });
+    }
+
+    private async Task<IActionResult> FinishInternal(
+        bool isRankUrl, ColosseumBattleFinishRequestDto req, CancellationToken ct)
+    {
+        if (!TryGetViewerId(out var vid)) return Unauthorized();
+
+        var run = await _runs.GetByViewerIdAsync(vid);
+        if (run is null)
+        {
+            return BadRequest(new { error = "arena_colosseum_no_active_run" });
+        }
+
+        // Match-result tracking: 1 = win, 2 = loss, 0 = draw/abort. Record_list mirrors
+        // ColosseumTopTask.battle_results.result_list (1=win, 0=loss). is_retire surfaces
+        // as a non-counted result — does not advance the bracket.
+        bool counts = req.IsRetire == 0;
+        if (counts)
+        {
+            bool isWin = req.BattleResult == 1;
+            run.BattleCountThisRound += 1;
+            if (isWin) run.WinCount += 1;
+            else run.LossCount += 1;
+
+            var resultList = ParseIntList(run.ResultListJson);
+            resultList.Add(isWin ? 1 : 0);
+            run.ResultListJson = JsonSerializer.Serialize(resultList);
+            await _runs.UpsertAsync(run);
+        }
+
+        // result_code 3502 ("battle already finished") is the idempotent-retry tolerance per
+        // FinishTaskBase.IsEffectiveErrorCode. Server emits standard data; the translation
+        // middleware sets the wire result_code via data_headers from the response envelope.
+        return Ok(new ColosseumBattleFinishResponseDto { BattleResult = req.BattleResult });
+    }
+
+    private static List<int> ParseIntList(string json) =>
+        string.IsNullOrEmpty(json)
+            ? new()
+            : JsonSerializer.Deserialize<List<int>>(json) ?? new();
+}
diff --git a/SVSim.EmulatedEntrypoint/Controllers/ArenaColosseumController.cs b/SVSim.EmulatedEntrypoint/Controllers/ArenaColosseumController.cs
index 45c8fefe..1dc1ab5b 100644
--- a/SVSim.EmulatedEntrypoint/Controllers/ArenaColosseumController.cs
+++ b/SVSim.EmulatedEntrypoint/Controllers/ArenaColosseumController.cs
@@ -12,6 +12,7 @@ using SVSim.EmulatedEntrypoint.Models.Dtos.Common.ArenaTwoPick;
 using SVSim.EmulatedEntrypoint.Models.Dtos.Requests;
 using SVSim.EmulatedEntrypoint.Models.Dtos.Requests.ArenaColosseum;
 using SVSim.EmulatedEntrypoint.Models.Dtos.Responses.ArenaColosseum;
+using SVSim.EmulatedEntrypoint.Services.ArenaColosseum;
 
 namespace SVSim.EmulatedEntrypoint.Controllers;
 
@@ -28,17 +29,20 @@ public class ArenaColosseumController : SVSimController
     private readonly IArenaColosseumRunRepository _runs;
     private readonly IInventoryService _inventory;
     private readonly IDeckRepository _decks;
+    private readonly IColosseumProgressionService _progression;
 
     public ArenaColosseumController(
         IGameConfigService config,
         IArenaColosseumRunRepository runs,
         IInventoryService inventory,
-        IDeckRepository decks)
+        IDeckRepository decks,
+        IColosseumProgressionService progression)
     {
         _config = config;
         _runs = runs;
         _inventory = inventory;
         _decks = decks;
+        _progression = progression;
     }
 
     [HttpPost("top")]
@@ -247,6 +251,104 @@ public class ArenaColosseumController : SVSimController
         return Ok(new { });
     }
 
+    [HttpPost("finish")]
+    public async Task<IActionResult> Finish([FromBody] BaseRequest _)
+    {
+        if (!TryGetViewerId(out var vid)) return Unauthorized();
+        var run = await _runs.GetByViewerIdAsync(vid);
+        if (run is null) return BadRequest(new { error = "no_active_run" });
+
+        var rounds = _config.Get<ColosseumRoundsConfig>();
+        var decision = _progression.DecideAdvancement(run, rounds);
+        if (!decision.IsBracketEnd)
+        {
+            return BadRequest(new { error = "bracket_not_finished" });
+        }
+
+        run.IsChampion = decision.IsChampion;
+        var rewardEntries = _progression.BuildFinishRewards(run, rounds);
+        var (wireRewards, wireRewardList) = await GrantRewardsAsync(vid, rewardEntries);
+
+        await _runs.DeleteAsync(vid);
+
+        return Ok(new FinishResponse
+        {
+            Rewards = wireRewards,
+            RewardList = wireRewardList,
+            ColosseumStatus = new ColosseumOwnStatus
+            {
+                NowRoundId = run.RoundId,
+                IsChampion = decision.IsChampion ? true : null,
+                ColosseumName = decision.IsChampion ? rounds.Rounds.Count > 0
+                    ? _config.Get<ColosseumSeasonConfig>().ColosseumName
+                    : null : null,
+            },
+        });
+    }
+
+    [HttpPost("retire")]
+    public async Task<IActionResult> Retire([FromBody] BaseRequest _)
+    {
+        if (!TryGetViewerId(out var vid)) return Unauthorized();
+        var run = await _runs.GetByViewerIdAsync(vid);
+        if (run is null) return BadRequest(new { error = "no_active_run" });
+
+        var rounds = _config.Get<ColosseumRoundsConfig>();
+        var rewardEntries = _progression.BuildRetireRewards(run, rounds);
+        var (wireRewards, wireRewardList) = await GrantRewardsAsync(vid, rewardEntries);
+
+        await _runs.DeleteAsync(vid);
+
+        return Ok(new FinishResponse
+        {
+            Rewards = wireRewards,
+            RewardList = wireRewardList,
+            ColosseumStatus = new ColosseumOwnStatus
+            {
+                NowRoundId = run.RoundId,
+                RestEntryNum = 0,
+            },
+        });
+    }
+
+    /// <summary>
+    /// Grant the bundle through <c>IInventoryTransaction.GrantAsync</c> per
+    /// <c>feedback_reward_grant_service</c> — single dispatch table for every UserGoodsType.
+    /// Returns the two wire forms (rich <c>rewards</c> receipt + wallet-delta <c>reward_list</c>).
+    /// </summary>
+    private async Task<(List<ColosseumReceivedReward>, List<RewardEntryDto>)> GrantRewardsAsync(
+        long viewerId, IReadOnlyList<ColosseumRoundsConfig.RewardEntry> bundle)
+    {
+        var receipts = new List<ColosseumReceivedReward>();
+        var deltas = new List<RewardEntryDto>();
+        if (bundle.Count == 0) return (receipts, deltas);
+
+        await using var tx = await _inventory.BeginAsync(viewerId);
+        foreach (var entry in bundle)
+        {
+            var granted = await tx.GrantAsync(entry.Type, entry.DetailId, entry.Count);
+            receipts.Add(new ColosseumReceivedReward
+            {
+                RewardNumber = entry.Count,
+                RewardType = (int)entry.Type,
+                RewardDetailId = entry.DetailId,
+                Name = entry.Name,
+            });
+            // GrantAsync returns one or more (RewardType, RewardId, RewardNum) tuples — the
+            // post-state-total semantics are owned by the inventory commit, which the wallet-delta
+            // reflection inherits via tx.CommitAsync below.
+            var first = granted.FirstOrDefault();
+            deltas.Add(new RewardEntryDto
+            {
+                RewardType = first is null ? (int)entry.Type : (int)first.RewardType,
+                RewardId = first?.RewardId ?? entry.DetailId,
+                RewardNum = first?.RewardNum ?? entry.Count,
+            });
+        }
+        await tx.CommitAsync();
+        return (receipts, deltas);
+    }
+
     private static int ResolveServerRoundId(ColosseumSeasonConfig season) => 1;
 
     private async Task<RewardEntryDto> DebitCrystalAsync(IInventoryTransaction tx, int cost)
diff --git a/SVSim.EmulatedEntrypoint/Models/Dtos/ArenaColosseum/BattleDoMatchingRequestDto.cs b/SVSim.EmulatedEntrypoint/Models/Dtos/ArenaColosseum/BattleDoMatchingRequestDto.cs
new file mode 100644
index 00000000..447d06d7
--- /dev/null
+++ b/SVSim.EmulatedEntrypoint/Models/Dtos/ArenaColosseum/BattleDoMatchingRequestDto.cs
@@ -0,0 +1,33 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+using SVSim.EmulatedEntrypoint.Models.Dtos.Requests;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.ArenaColosseum;
+
+/// <summary>
+/// <c>POST /colosseum_battle/do_matching</c> + <c>POST /colosseum_rank_battle/do_matching</c>.
+/// Standard <c>DoMatchingParam</c> wire shape — same fields as rank/free-battle's variant.
+/// Per do-matching.md, post-promotion the client forces <c>need_init = 0</c>, but the
+/// server tolerates either value (URL is the routing signal).
+/// </summary>
+[MessagePackObject]
+public sealed class ColosseumDoMatchingRequestDto : BaseRequest
+{
+    [JsonPropertyName("need_init")] [Key("need_init")]
+    public int NeedInit { get; set; }
+
+    [JsonPropertyName("card_master_hash")] [Key("card_master_hash")]
+    public string? CardMasterHash { get; set; }
+
+    [JsonPropertyName("log")] [Key("log")]
+    public int Log { get; set; }
+
+    [JsonPropertyName("use_stage_select")] [Key("use_stage_select")]
+    public int UseStageSelect { get; set; }
+
+    [JsonPropertyName("excluded_field_id_list")] [Key("excluded_field_id_list")]
+    public List<long> ExcludedFieldIdList { get; set; } = new();
+
+    [JsonPropertyName("is_default_skin")] [Key("is_default_skin")]
+    public int IsDefaultSkin { get; set; }
+}
diff --git a/SVSim.EmulatedEntrypoint/Models/Dtos/ArenaColosseum/BattleFinishRequestDto.cs b/SVSim.EmulatedEntrypoint/Models/Dtos/ArenaColosseum/BattleFinishRequestDto.cs
new file mode 100644
index 00000000..32c766e6
--- /dev/null
+++ b/SVSim.EmulatedEntrypoint/Models/Dtos/ArenaColosseum/BattleFinishRequestDto.cs
@@ -0,0 +1,49 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+using SVSim.EmulatedEntrypoint.Models.Dtos.Requests;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.ArenaColosseum;
+
+/// <summary>
+/// <c>POST /colosseum_battle/finish</c> + <c>POST /colosseum_rank_battle/finish</c> request
+/// body — the per-match finish, NOT the bracket-end <c>/arena_colosseum/finish</c>.
+/// Standard <c>BattleFinishParam</c> shape inherited from <c>FinishTaskBase</c>.
+/// </summary>
+[MessagePackObject]
+public sealed class ColosseumBattleFinishRequestDto : BaseRequest
+{
+    [JsonPropertyName("battle_result")] [Key("battle_result")]
+    public int BattleResult { get; set; }
+
+    [JsonPropertyName("is_retire")] [Key("is_retire")]
+    public int IsRetire { get; set; }
+
+    [JsonPropertyName("recovery_data")] [Key("recovery_data")]
+    public string? RecoveryData { get; set; }
+
+    [JsonPropertyName("class_id")] [Key("class_id")]
+    public int ClassId { get; set; }
+
+    [JsonPropertyName("total_turn")] [Key("total_turn")]
+    public int TotalTurn { get; set; }
+
+    [JsonPropertyName("evolve_count")] [Key("evolve_count")]
+    public int EvolveCount { get; set; }
+
+    [JsonPropertyName("enemy_evolve_count")] [Key("enemy_evolve_count")]
+    public int EnemyEvolveCount { get; set; }
+}
+
+/// <summary>
+/// <c>colosseum_battle/finish</c> response. Per battle-finish.md, the client maps this to
+/// <c>ColosseumBattleFinishDetail</c> which is an empty <c>MatchFinishBase</c> subclass —
+/// no Colosseum-specific fields beyond the shared rank-battle-finish superset. Phase 2 v1
+/// emits the minimum required to keep the client's <c>BattleFinishResponsProcessing</c>
+/// happy.
+/// </summary>
+[MessagePackObject(keyAsPropertyName: true)]
+public sealed class ColosseumBattleFinishResponseDto
+{
+    [JsonPropertyName("battle_result")] [Key("battle_result")]
+    public int BattleResult { get; set; }
+}
diff --git a/SVSim.EmulatedEntrypoint/Models/Dtos/ArenaColosseum/ColosseumReceivedReward.cs b/SVSim.EmulatedEntrypoint/Models/Dtos/ArenaColosseum/ColosseumReceivedReward.cs
new file mode 100644
index 00000000..224cf3cc
--- /dev/null
+++ b/SVSim.EmulatedEntrypoint/Models/Dtos/ArenaColosseum/ColosseumReceivedReward.cs
@@ -0,0 +1,26 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.ArenaColosseum;
+
+/// <summary>
+/// Per-entry shape for the <c>rewards</c> array on <c>/finish</c> + <c>/retire</c>. Richer
+/// than <c>RewardEntryDto</c> (which is the <c>reward_list</c> shape) — carries a display
+/// name. Distinct from the wallet-delta block: client renders <c>rewards</c> in the
+/// post-bracket popup while <c>reward_list</c> drives the silent wallet update.
+/// </summary>
+[MessagePackObject]
+public sealed class ColosseumReceivedReward
+{
+    [JsonPropertyName("reward_number")] [Key("reward_number")]
+    public int RewardNumber { get; set; }
+
+    [JsonPropertyName("reward_type")] [Key("reward_type")]
+    public int RewardType { get; set; }
+
+    [JsonPropertyName("reward_detail_id")] [Key("reward_detail_id")]
+    public long RewardDetailId { get; set; }
+
+    [JsonPropertyName("name")] [Key("name")]
+    public string Name { get; set; } = "";
+}
diff --git a/SVSim.EmulatedEntrypoint/Models/Dtos/Responses/ArenaColosseum/FinishResponse.cs b/SVSim.EmulatedEntrypoint/Models/Dtos/Responses/ArenaColosseum/FinishResponse.cs
new file mode 100644
index 00000000..a4f646ef
--- /dev/null
+++ b/SVSim.EmulatedEntrypoint/Models/Dtos/Responses/ArenaColosseum/FinishResponse.cs
@@ -0,0 +1,27 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+using SVSim.EmulatedEntrypoint.Models.Dtos.ArenaColosseum;
+using SVSim.EmulatedEntrypoint.Models.Dtos.Common.ArenaTwoPick;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Responses.ArenaColosseum;
+
+/// <summary>
+/// <c>POST /arena_colosseum/finish</c> and <c>POST /arena_colosseum/retire</c>. Wire-identical
+/// shape per finish.md §"Wire-shared with /retire" — endpoints differ in side-effects only:
+/// /finish emits per-round-completion + champion bonus and marks the entry champion;
+/// /retire emits the round-capped consolation. The client renders <c>rewards</c> in the
+/// post-bracket popup, applies wallet deltas via <c>reward_list</c>, and updates the
+/// status block via <c>colosseum_status</c>.
+/// </summary>
+[MessagePackObject]
+public sealed class FinishResponse
+{
+    [JsonPropertyName("rewards")] [Key("rewards")]
+    public List<ColosseumReceivedReward> Rewards { get; set; } = new();
+
+    [JsonPropertyName("reward_list")] [Key("reward_list")]
+    public List<RewardEntryDto> RewardList { get; set; } = new();
+
+    [JsonPropertyName("colosseum_status")] [Key("colosseum_status")]
+    public ColosseumOwnStatus ColosseumStatus { get; set; } = new();
+}
diff --git a/SVSim.EmulatedEntrypoint/Program.cs b/SVSim.EmulatedEntrypoint/Program.cs
index f2edf596..16a7ab6b 100644
--- a/SVSim.EmulatedEntrypoint/Program.cs
+++ b/SVSim.EmulatedEntrypoint/Program.cs
@@ -107,6 +107,8 @@ public class Program
         builder.Services.AddScoped<IViewerStoryProgressRepository, ViewerStoryProgressRepository>();
         builder.Services.AddScoped<IArenaTwoPickRunRepository, ArenaTwoPickRunRepository>();
         builder.Services.AddScoped<IArenaColosseumRunRepository, ArenaColosseumRunRepository>();
+        builder.Services.AddScoped<SVSim.EmulatedEntrypoint.Services.ArenaColosseum.IColosseumProgressionService,
+                                   SVSim.EmulatedEntrypoint.Services.ArenaColosseum.ColosseumProgressionService>();
         builder.Services.AddScoped<IArenaTwoPickCardPoolService, ArenaTwoPickCardPoolService>();
         builder.Services.AddScoped<IArenaTwoPickService, ArenaTwoPickService>();
         builder.Services.AddScoped<IMatchContextBuilder, MatchContextBuilder>();
@@ -158,6 +160,11 @@ public class Program
             // (see Shadowverse_Code_2026-05-23/ApiType.cs), so PvpOnly: park forever, no AI fallback.
             new ModePolicy("rotation_free_battle", PolicyKind.PvpOnly),
             new ModePolicy("unlimited_free_battle", PolicyKind.PvpOnly),
+            // Colosseum (Grand Prix). Pre-promotion + post-promotion (rank) URLs each map
+            // to their own pair-up mode — the URL IS the signal per do-matching.md, and the
+            // node session has no way to ask the client "which bracket are you in?".
+            new ModePolicy("colosseum_battle", PolicyKind.PvpOnly),
+            new ModePolicy("colosseum_rank_battle", PolicyKind.PvpOnly),
         }));
         builder.Services.AddSingleton<IMatchingPairUpService, InProcessPairUp>();
         // Single resolver shared by every /do_matching family controller. Owns the
diff --git a/SVSim.EmulatedEntrypoint/Services/ArenaColosseum/ColosseumProgressionService.cs b/SVSim.EmulatedEntrypoint/Services/ArenaColosseum/ColosseumProgressionService.cs
new file mode 100644
index 00000000..a07abfe4
--- /dev/null
+++ b/SVSim.EmulatedEntrypoint/Services/ArenaColosseum/ColosseumProgressionService.cs
@@ -0,0 +1,69 @@
+using SVSim.Database.Models;
+using SVSim.Database.Models.Config;
+
+namespace SVSim.EmulatedEntrypoint.Services.ArenaColosseum;
+
+public class ColosseumProgressionService : IColosseumProgressionService
+{
+    /// <summary>Colosseum-specific node signal — see do-matching.md §matching_state 3008.</summary>
+    public const int PromoteToRankMatchingState = 3008;
+
+    public bool ShouldPromoteToRankMatching(ViewerArenaColosseumRun run, int matchingState) =>
+        matchingState == PromoteToRankMatchingState && !run.IsRankMatching;
+
+    public AdvancementDecision DecideAdvancement(ViewerArenaColosseumRun run, ColosseumRoundsConfig rounds)
+    {
+        var currentRound = rounds.Rounds.FirstOrDefault(r => r.RoundId == run.RoundId);
+        var currentGroup = currentRound?.Groups.FirstOrDefault();
+        var maxRoundId = rounds.Rounds.Count == 0 ? run.RoundId : rounds.Rounds.Max(r => r.RoundId);
+
+        // No matching round config (e.g. content not seeded) — treat current state as terminal
+        // so the controller doesn't loop forever. Champion=false because we can't tell.
+        if (currentGroup is null)
+        {
+            return new AdvancementDecision(run.RoundId, IsBracketEnd: true, IsChampion: false);
+        }
+
+        // Cleared the breakthrough threshold this round.
+        if (run.WinCount >= currentGroup.BreakthroughNumber)
+        {
+            bool isFinal = run.RoundId >= maxRoundId;
+            return new AdvancementDecision(
+                NextRoundId: isFinal ? run.RoundId : run.RoundId + 1,
+                IsBracketEnd: isFinal,
+                IsChampion: isFinal);
+        }
+
+        // Exhausted the per-round battle cap without clearing — bracket ends at current round.
+        if (run.BattleCountThisRound >= currentGroup.MaxBattleCount)
+        {
+            return new AdvancementDecision(run.RoundId, IsBracketEnd: true, IsChampion: false);
+        }
+
+        // Mid-round, still playing.
+        return new AdvancementDecision(run.RoundId, IsBracketEnd: false, IsChampion: false);
+    }
+
+    public IReadOnlyList<ColosseumRoundsConfig.RewardEntry> BuildRetireRewards(
+        ViewerArenaColosseumRun run, ColosseumRoundsConfig rounds)
+    {
+        var round = rounds.Rounds.FirstOrDefault(r => r.RoundId == run.RoundId);
+        return round?.RetireRewards ?? new();
+    }
+
+    public IReadOnlyList<ColosseumRoundsConfig.RewardEntry> BuildFinishRewards(
+        ViewerArenaColosseumRun run, ColosseumRoundsConfig rounds)
+    {
+        var round = rounds.Rounds.FirstOrDefault(r => r.RoundId == run.RoundId);
+        var bundle = new List<ColosseumRoundsConfig.RewardEntry>();
+        if (round is not null)
+        {
+            bundle.AddRange(round.FinishRewards);
+        }
+        if (run.IsChampion)
+        {
+            bundle.AddRange(rounds.ChampionRewards);
+        }
+        return bundle;
+    }
+}
diff --git a/SVSim.EmulatedEntrypoint/Services/ArenaColosseum/IColosseumProgressionService.cs b/SVSim.EmulatedEntrypoint/Services/ArenaColosseum/IColosseumProgressionService.cs
new file mode 100644
index 00000000..9c58afc0
--- /dev/null
+++ b/SVSim.EmulatedEntrypoint/Services/ArenaColosseum/IColosseumProgressionService.cs
@@ -0,0 +1,39 @@
+using SVSim.Database.Enums;
+using SVSim.Database.Models;
+using SVSim.Database.Models.Config;
+
+namespace SVSim.EmulatedEntrypoint.Services.ArenaColosseum;
+
+/// <summary>
+/// Pure-logic decisions for the Colosseum bracket lifecycle. Reads a
+/// <see cref="ViewerArenaColosseumRun"/> + <see cref="ColosseumRoundsConfig"/> snapshot and
+/// returns advancement / promotion / reward decisions. Side-effectful (debits, grants,
+/// run-row writes) live on the controllers — this service just computes.
+/// </summary>
+public interface IColosseumProgressionService
+{
+    /// <summary>True when the node signal <c>matching_state == 3008</c> indicates the run
+    /// has been promoted to the ranked bracket and we haven't already flipped the flag.
+    /// Subsequent battle URLs route to <c>colosseum_rank_battle/*</c>.</summary>
+    bool ShouldPromoteToRankMatching(ViewerArenaColosseumRun run, int matchingState);
+
+    /// <summary>Triggered post-match-finish when wins/losses cross thresholds. Returns the
+    /// next round id (or current if no change), whether the bracket has ended, and the
+    /// champion flag for the final-round-cleared case.</summary>
+    AdvancementDecision DecideAdvancement(ViewerArenaColosseumRun run, ColosseumRoundsConfig rounds);
+
+    /// <summary>Bundle to grant on <c>/retire</c>. Reads
+    /// <see cref="ColosseumRoundsConfig.RoundEntry.RetireRewards"/> for the run's
+    /// <see cref="ViewerArenaColosseumRun.RoundId"/>. Empty when no matching round.</summary>
+    IReadOnlyList<ColosseumRoundsConfig.RewardEntry> BuildRetireRewards(
+        ViewerArenaColosseumRun run, ColosseumRoundsConfig rounds);
+
+    /// <summary>Bundle to grant on <c>/finish</c>. Combines the current round's
+    /// <see cref="ColosseumRoundsConfig.RoundEntry.FinishRewards"/> with
+    /// <see cref="ColosseumRoundsConfig.ChampionRewards"/> when the run is a champion.</summary>
+    IReadOnlyList<ColosseumRoundsConfig.RewardEntry> BuildFinishRewards(
+        ViewerArenaColosseumRun run, ColosseumRoundsConfig rounds);
+}
+
+/// <summary>Output of <see cref="IColosseumProgressionService.DecideAdvancement"/>.</summary>
+public sealed record AdvancementDecision(int NextRoundId, bool IsBracketEnd, bool IsChampion);
diff --git a/SVSim.EmulatedEntrypoint/Services/IMatchContextBuilder.cs b/SVSim.EmulatedEntrypoint/Services/IMatchContextBuilder.cs
index 84c9a83c..a40efd0a 100644
--- a/SVSim.EmulatedEntrypoint/Services/IMatchContextBuilder.cs
+++ b/SVSim.EmulatedEntrypoint/Services/IMatchContextBuilder.cs
@@ -24,4 +24,13 @@ public interface IMatchContextBuilder
     /// no deck at that slot.
     /// </summary>
     Task<MatchContext> BuildForRankBattleAsync(long viewerId, Format format, int deckNo);
+
+    /// <summary>
+    /// Build a context for an Arena Colosseum bracket match — reads the active
+    /// <c>ViewerArenaColosseumRun</c>'s registered deck slot (single-deck v1) via
+    /// <c>IDeckRepository.GetDeck</c> (NOT viewer-graph traversal per
+    /// <c>project_ef_nav_include_pitfall</c>). Throws when the run is missing or no deck
+    /// has been registered yet.
+    /// </summary>
+    Task<MatchContext> BuildForColosseumAsync(long viewerId);
 }
diff --git a/SVSim.EmulatedEntrypoint/Services/MatchContextBuilder.cs b/SVSim.EmulatedEntrypoint/Services/MatchContextBuilder.cs
index 9b827c4e..f4b5e9f7 100644
--- a/SVSim.EmulatedEntrypoint/Services/MatchContextBuilder.cs
+++ b/SVSim.EmulatedEntrypoint/Services/MatchContextBuilder.cs
@@ -11,17 +11,20 @@ namespace SVSim.EmulatedEntrypoint.Services;
 public class MatchContextBuilder : IMatchContextBuilder
 {
     private readonly IArenaTwoPickRunRepository _runs;
+    private readonly IArenaColosseumRunRepository _colosseumRuns;
     private readonly IViewerRepository _viewers;
     private readonly IDeckRepository _decks;
     private readonly IGameConfigService _config;
 
     public MatchContextBuilder(
         IArenaTwoPickRunRepository runs,
+        IArenaColosseumRunRepository colosseumRuns,
         IViewerRepository viewers,
         IDeckRepository decks,
         IGameConfigService config)
     {
         _runs = runs;
+        _colosseumRuns = colosseumRuns;
         _viewers = viewers;
         _decks = decks;
         _config = config;
@@ -120,4 +123,58 @@ public class MatchContextBuilder : IMatchContextBuilder
             IsOfficial: viewer.Info.IsOfficial ? 1 : 0,
             BattleModeId: BattleModes.TakeTwo);
     }
+
+    public async Task<MatchContext> BuildForColosseumAsync(long viewerId)
+    {
+        var run = await _colosseumRuns.GetByViewerIdAsync(viewerId)
+            ?? throw new InvalidOperationException("arena_colosseum_no_active_run");
+
+        // v1 single-deck slot — Round-3 multi-deck format is deferred per plan.
+        var deckNos = JsonSerializer.Deserialize<List<int>>(run.RegisteredDeckNoListJson) ?? new();
+        if (deckNos.Count == 0)
+        {
+            throw new InvalidOperationException("arena_colosseum_no_deck_registered");
+        }
+        var deckNo = deckNos[0];
+
+        var viewer = await _viewers.LoadForMatchContextAsync(viewerId)
+            ?? throw new InvalidOperationException($"viewer {viewerId} not found");
+
+        var deck = await _decks.GetDeck(viewerId, run.DeckFormat, deckNo)
+            ?? throw new InvalidOperationException(
+                $"viewer {viewerId} has no deck #{deckNo} for format {run.DeckFormat}");
+
+        var defaults = _config.Get<DefaultLoadoutConfig>();
+        var emblemId = viewer.Info.SelectedEmblem.Id != 0
+            ? viewer.Info.SelectedEmblem.Id.ToString()
+            : defaults.EmblemId.ToString();
+        var degreeId = viewer.Info.SelectedDegree.Id != 0
+            ? viewer.Info.SelectedDegree.Id.ToString()
+            : defaults.DegreeId.ToString();
+        var charaId = run.LeaderSkinId != 0
+            ? run.LeaderSkinId.ToString()
+            : deck.LeaderSkin.Id != 0
+                ? deck.LeaderSkin.Id.ToString()
+                : deck.Class.Id.ToString();
+        var sleeveId = deck.Sleeve.Id != 0
+            ? deck.Sleeve.Id.ToString()
+            : defaults.SleeveId.ToString();
+        var deckCardIds = deck.Cards
+            .SelectMany(c => Enumerable.Repeat(c.Card.Id, c.Count))
+            .ToList();
+
+        return new MatchContext(
+            SelfDeckCardIds: deckCardIds,
+            ClassId: (CardClass)deck.Class.Id,
+            CharaId: charaId,
+            CardMasterName: "card_master_node_10015",
+            CountryCode: viewer.Info.CountryCode ?? string.Empty,
+            UserName: viewer.DisplayName,
+            SleeveId: sleeveId,
+            EmblemId: emblemId,
+            DegreeId: degreeId,
+            FieldId: 43,
+            IsOfficial: viewer.Info.IsOfficial ? 1 : 0,
+            BattleModeId: BattleModes.TakeTwo);
+    }
 }
diff --git a/SVSim.UnitTests/Controllers/ArenaColosseumBattleControllerTests.cs b/SVSim.UnitTests/Controllers/ArenaColosseumBattleControllerTests.cs
new file mode 100644
index 00000000..07cc21a7
--- /dev/null
+++ b/SVSim.UnitTests/Controllers/ArenaColosseumBattleControllerTests.cs
@@ -0,0 +1,156 @@
+using System.Net;
+using System.Net.Http.Json;
+using System.Text.Json;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.DependencyInjection;
+using SVSim.Database;
+using SVSim.Database.Enums;
+using SVSim.Database.Models;
+using SVSim.UnitTests.Infrastructure;
+
+namespace SVSim.UnitTests.Controllers;
+
+/// <summary>
+/// Per-match battle URL coverage — verifies the dual <c>colosseum_battle/*</c> +
+/// <c>colosseum_rank_battle/*</c> dispatch matches <c>run.IsRankMatching</c>, that
+/// <c>battle/finish</c> bumps the per-round counters, and that the 3008 promotion
+/// trigger flips the run's rank flag.
+/// </summary>
+public class ArenaColosseumBattleControllerTests
+{
+    private static readonly object Envelope =
+        new { viewer_id = "0", steam_id = 0, steam_session_ticket = "" };
+
+    private static async Task SeedRunAsync(SVSimTestFactory factory, long viewerId, bool isRankMatching = false)
+    {
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+        db.ViewerArenaColosseumRuns.Add(new ViewerArenaColosseumRun
+        {
+            ViewerId = viewerId,
+            EntryId = 1001,
+            SeasonId = 42,
+            RoundId = 1,
+            DeckFormat = Format.Rotation,
+            MaxBattleCountThisRound = 5,
+            BreakthroughNumberThisRound = 4,
+            IsRankMatching = isRankMatching,
+            RegisteredDeckNoListJson = "[3]",
+        });
+        await db.SaveChangesAsync();
+    }
+
+    [Test]
+    public async Task DoMatching_pre_rank_rejects_when_run_is_rank_matching()
+    {
+        using var factory = new SVSimTestFactory();
+        var vid = await factory.SeedViewerAsync();
+        await SeedRunAsync(factory, vid, isRankMatching: true);
+        await factory.SeedDeckAsync(vid, Format.Rotation, number: 3);
+        using var client = factory.CreateAuthenticatedClient(vid);
+
+        var resp = await client.PostAsync("/colosseum_battle/do_matching", JsonContent.Create(Envelope));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.BadRequest));
+        var body = await resp.Content.ReadAsStringAsync();
+        StringAssert.Contains("colosseum_url_phase_mismatch", body);
+    }
+
+    [Test]
+    public async Task DoMatching_post_rank_rejects_when_run_is_pre_rank()
+    {
+        using var factory = new SVSimTestFactory();
+        var vid = await factory.SeedViewerAsync();
+        await SeedRunAsync(factory, vid, isRankMatching: false);
+        await factory.SeedDeckAsync(vid, Format.Rotation, number: 3);
+        using var client = factory.CreateAuthenticatedClient(vid);
+
+        var resp = await client.PostAsync("/colosseum_rank_battle/do_matching", JsonContent.Create(Envelope));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.BadRequest));
+        var body = await resp.Content.ReadAsStringAsync();
+        StringAssert.Contains("colosseum_url_phase_mismatch", body);
+    }
+
+    [Test]
+    public async Task DoMatching_returns_3001_when_no_deck_registered()
+    {
+        using var factory = new SVSimTestFactory();
+        var vid = await factory.SeedViewerAsync();
+
+        using (var scope = factory.Services.CreateScope())
+        {
+            var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+            db.ViewerArenaColosseumRuns.Add(new ViewerArenaColosseumRun
+            {
+                ViewerId = vid,
+                EntryId = 1001,
+                SeasonId = 42,
+                RoundId = 1,
+                DeckFormat = Format.Rotation,
+                RegisteredDeckNoListJson = "[]",
+            });
+            await db.SaveChangesAsync();
+        }
+
+        using var client = factory.CreateAuthenticatedClient(vid);
+        var resp = await client.PostAsync("/colosseum_battle/do_matching", JsonContent.Create(Envelope));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+
+        var body = await resp.Content.ReadAsStringAsync();
+        using var doc = JsonDocument.Parse(body);
+        Assert.That(doc.RootElement.GetProperty("matching_state").GetInt32(), Is.EqualTo(3001));
+    }
+
+    [Test]
+    public async Task BattleFinish_win_advances_counters_and_appends_result_list()
+    {
+        using var factory = new SVSimTestFactory();
+        var vid = await factory.SeedViewerAsync();
+        await SeedRunAsync(factory, vid);
+        using var client = factory.CreateAuthenticatedClient(vid);
+
+        var req = new
+        {
+            battle_result = 1, is_retire = 0, class_id = 1,
+            total_turn = 5, evolve_count = 1, enemy_evolve_count = 0,
+            recovery_data = "",
+            viewer_id = "0", steam_id = 0, steam_session_ticket = "",
+        };
+        var resp = await client.PostAsync("/colosseum_battle/finish", JsonContent.Create(req));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+        var run = await db.ViewerArenaColosseumRuns.FirstAsync(r => r.ViewerId == vid);
+        Assert.That(run.WinCount, Is.EqualTo(1));
+        Assert.That(run.LossCount, Is.EqualTo(0));
+        Assert.That(run.BattleCountThisRound, Is.EqualTo(1));
+        Assert.That(run.ResultListJson, Is.EqualTo("[1]"));
+    }
+
+    [Test]
+    public async Task BattleFinish_retire_does_not_advance_counters()
+    {
+        using var factory = new SVSimTestFactory();
+        var vid = await factory.SeedViewerAsync();
+        await SeedRunAsync(factory, vid);
+        using var client = factory.CreateAuthenticatedClient(vid);
+
+        var req = new
+        {
+            battle_result = 2, is_retire = 1, class_id = 1,
+            total_turn = 3, evolve_count = 0, enemy_evolve_count = 0,
+            recovery_data = "",
+            viewer_id = "0", steam_id = 0, steam_session_ticket = "",
+        };
+        var resp = await client.PostAsync("/colosseum_battle/finish", JsonContent.Create(req));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+        var run = await db.ViewerArenaColosseumRuns.FirstAsync(r => r.ViewerId == vid);
+        Assert.That(run.WinCount, Is.EqualTo(0));
+        Assert.That(run.LossCount, Is.EqualTo(0));
+        Assert.That(run.BattleCountThisRound, Is.EqualTo(0),
+            "is_retire=1 must not bump the per-round battle counter");
+    }
+}
diff --git a/SVSim.UnitTests/Controllers/ArenaColosseumControllerBracketTerminateTests.cs b/SVSim.UnitTests/Controllers/ArenaColosseumControllerBracketTerminateTests.cs
new file mode 100644
index 00000000..017ca313
--- /dev/null
+++ b/SVSim.UnitTests/Controllers/ArenaColosseumControllerBracketTerminateTests.cs
@@ -0,0 +1,244 @@
+using System.Net;
+using System.Net.Http.Json;
+using System.Text.Json;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.DependencyInjection;
+using SVSim.Database;
+using SVSim.Database.Enums;
+using SVSim.Database.Models;
+using SVSim.UnitTests.Infrastructure;
+
+namespace SVSim.UnitTests.Controllers;
+
+/// <summary>
+/// Bracket-end /finish + /retire coverage. Locks the wire shape (rewards + reward_list +
+/// colosseum_status) and verifies side-effects: rewards granted through the inventory
+/// service, run row deleted, champion flag flipped on final-round clear.
+/// </summary>
+public class ArenaColosseumControllerBracketTerminateTests
+{
+    private static readonly object Envelope =
+        new { viewer_id = "0", steam_id = 0, steam_session_ticket = "" };
+
+    /// <summary>Three-round config with reward bundles on every round + a champion bundle.</summary>
+    private static async Task ActivateSeasonWithRewardsAsync(SVSimTestFactory factory)
+    {
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+
+        var seasonJson = JsonSerializer.Serialize(new
+        {
+            IsColosseumPeriod = true,
+            SeasonId = 42,
+            ColosseumName = "Test Cup",
+            DeckFormat = (int)Format.Rotation,
+            FinalRoundEliminateCount = 1000,
+        });
+        await UpsertConfigAsync(db, "ColosseumSeason", seasonJson);
+
+        var roundsJson = JsonSerializer.Serialize(new
+        {
+            Rounds = new[]
+            {
+                new
+                {
+                    RoundId = 1,
+                    Groups = new[] { new { Group = "", MaxBattleCount = 5, BreakthroughNumber = 3, EntryNumber = 100_000 } },
+                    FinishRewards = new[]
+                    {
+                        new { Type = (int)UserGoodsType.Crystal, DetailId = 0L, Count = 100, Name = "R1 finish" },
+                    },
+                    RetireRewards = new object[]
+                    {
+                        new { Type = (int)UserGoodsType.Rupy, DetailId = 0L, Count = 50, Name = "R1 retire" },
+                    },
+                },
+                new
+                {
+                    RoundId = 2,
+                    Groups = new[] { new { Group = "Group A", MaxBattleCount = 5, BreakthroughNumber = 4, EntryNumber = 10_000 } },
+                    FinishRewards = new[]
+                    {
+                        new { Type = (int)UserGoodsType.Crystal, DetailId = 0L, Count = 250, Name = "R2 finish" },
+                    },
+                    RetireRewards = Array.Empty<object>(),
+                },
+                new
+                {
+                    RoundId = 3,
+                    Groups = new[] { new { Group = "Final", MaxBattleCount = 5, BreakthroughNumber = 4, EntryNumber = 1_000 } },
+                    FinishRewards = new[]
+                    {
+                        new { Type = (int)UserGoodsType.Crystal, DetailId = 0L, Count = 1000, Name = "Final clear" },
+                    },
+                    RetireRewards = Array.Empty<object>(),
+                },
+            },
+            ChampionRewards = new[]
+            {
+                new { Type = (int)UserGoodsType.Crystal, DetailId = 0L, Count = 5000, Name = "Champion Pack" },
+            },
+        });
+        await UpsertConfigAsync(db, "ColosseumRounds", roundsJson);
+    }
+
+    private static async Task UpsertConfigAsync(SVSimDbContext db, string section, string json)
+    {
+        var existing = await db.GameConfigs.FirstOrDefaultAsync(s => s.SectionName == section);
+        if (existing is null)
+            db.GameConfigs.Add(new GameConfigSection { SectionName = section, ValueJson = json });
+        else
+            existing.ValueJson = json;
+        await db.SaveChangesAsync();
+    }
+
+    private static async Task SeedRunAsync(
+        SVSimTestFactory factory, long viewerId, int roundId, int winCount, int battleCount)
+    {
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+        db.ViewerArenaColosseumRuns.Add(new ViewerArenaColosseumRun
+        {
+            ViewerId = viewerId,
+            EntryId = 1001,
+            SeasonId = 42,
+            RoundId = roundId,
+            DeckFormat = Format.Rotation,
+            WinCount = winCount,
+            BattleCountThisRound = battleCount,
+            MaxBattleCountThisRound = 5,
+            BreakthroughNumberThisRound = roundId == 1 ? 3 : 4,
+        });
+        await db.SaveChangesAsync();
+    }
+
+    [Test]
+    public async Task Finish_emits_champion_flag_when_round_3_cleared()
+    {
+        using var factory = new SVSimTestFactory();
+        await ActivateSeasonWithRewardsAsync(factory);
+        var vid = await factory.SeedViewerAsync();
+        await SeedRunAsync(factory, vid, roundId: 3, winCount: 4, battleCount: 4);
+
+        using var client = factory.CreateAuthenticatedClient(vid);
+        var resp = await client.PostAsync("/arena_colosseum/finish", JsonContent.Create(Envelope));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+
+        var body = await resp.Content.ReadAsStringAsync();
+        using var doc = JsonDocument.Parse(body);
+        var root = doc.RootElement;
+
+        Assert.That(root.GetProperty("colosseum_status").GetProperty("is_champion").GetBoolean(), Is.True);
+        Assert.That(root.GetProperty("colosseum_status").GetProperty("colosseum_name").GetString(),
+            Is.EqualTo("Test Cup"));
+
+        // Final clear + champion bundle = 2 reward entries.
+        Assert.That(root.GetProperty("rewards").GetArrayLength(), Is.EqualTo(2));
+        Assert.That(root.GetProperty("reward_list").GetArrayLength(), Is.EqualTo(2));
+    }
+
+    [Test]
+    public async Task Finish_grants_rewards_and_deletes_run()
+    {
+        using var factory = new SVSimTestFactory();
+        await ActivateSeasonWithRewardsAsync(factory);
+        var vid = await factory.SeedViewerAsync();
+        // Round 1 breakthrough advances to round 2 — bracket isn't finished. Use round 3 +
+        // exhausted battle cap WITHOUT breakthrough to terminate cleanly with round-end rewards.
+        await SeedRunAsync(factory, vid, roundId: 3, winCount: 2, battleCount: 5);
+
+        ulong crystalsBefore;
+        using (var beforeScope = factory.Services.CreateScope())
+        {
+            var beforeDb = beforeScope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+            crystalsBefore = (await beforeDb.Viewers.FirstAsync(v => v.Id == vid)).Currency.Crystals;
+        }
+
+        using var client = factory.CreateAuthenticatedClient(vid);
+        var resp = await client.PostAsync("/arena_colosseum/finish", JsonContent.Create(Envelope));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+
+        using var verifyScope = factory.Services.CreateScope();
+        var db = verifyScope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+
+        var run = await db.ViewerArenaColosseumRuns.FirstOrDefaultAsync(r => r.ViewerId == vid);
+        Assert.That(run, Is.Null, "run row must be deleted on /finish");
+
+        var viewer = await db.Viewers.FirstAsync(v => v.Id == vid);
+        Assert.That(viewer.Currency.Crystals - crystalsBefore, Is.EqualTo(1000UL),
+            "Round 3 finish bundle is 1000 Crystal (not champion — battle cap hit without breakthrough)");
+    }
+
+    [Test]
+    public async Task Finish_rejects_when_bracket_still_in_progress()
+    {
+        using var factory = new SVSimTestFactory();
+        await ActivateSeasonWithRewardsAsync(factory);
+        var vid = await factory.SeedViewerAsync();
+        // Mid-round: 1 win, 1 battle, breakthrough is 3 — not yet eligible.
+        await SeedRunAsync(factory, vid, roundId: 1, winCount: 1, battleCount: 1);
+
+        using var client = factory.CreateAuthenticatedClient(vid);
+        var resp = await client.PostAsync("/arena_colosseum/finish", JsonContent.Create(Envelope));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.BadRequest));
+
+        var body = await resp.Content.ReadAsStringAsync();
+        StringAssert.Contains("bracket_not_finished", body);
+    }
+
+    [Test]
+    public async Task Retire_grants_round_capped_rewards_and_deletes_run()
+    {
+        using var factory = new SVSimTestFactory();
+        await ActivateSeasonWithRewardsAsync(factory);
+        var vid = await factory.SeedViewerAsync();
+        await SeedRunAsync(factory, vid, roundId: 1, winCount: 1, battleCount: 2);
+
+        ulong rupeesBefore;
+        using (var beforeScope = factory.Services.CreateScope())
+        {
+            var beforeDb = beforeScope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+            rupeesBefore = (await beforeDb.Viewers.FirstAsync(v => v.Id == vid)).Currency.Rupees;
+        }
+
+        using var client = factory.CreateAuthenticatedClient(vid);
+        var resp = await client.PostAsync("/arena_colosseum/retire", JsonContent.Create(Envelope));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+
+        var body = await resp.Content.ReadAsStringAsync();
+        using var doc = JsonDocument.Parse(body);
+        var root = doc.RootElement;
+        Assert.That(root.GetProperty("rewards").GetArrayLength(), Is.EqualTo(1));
+        Assert.That(root.GetProperty("rewards")[0].GetProperty("name").GetString(), Is.EqualTo("R1 retire"));
+
+        using var verifyScope = factory.Services.CreateScope();
+        var db = verifyScope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+        var run = await db.ViewerArenaColosseumRuns.FirstOrDefaultAsync(r => r.ViewerId == vid);
+        Assert.That(run, Is.Null, "run row must be deleted on /retire");
+
+        var viewer = await db.Viewers.FirstAsync(v => v.Id == vid);
+        Assert.That(viewer.Currency.Rupees - rupeesBefore, Is.EqualTo(50UL),
+            "Round 1 retire bundle adds 50 Rupy on top of starting balance");
+    }
+
+    [Test]
+    public async Task Retire_during_final_round_still_works_and_emits_status()
+    {
+        using var factory = new SVSimTestFactory();
+        await ActivateSeasonWithRewardsAsync(factory);
+        var vid = await factory.SeedViewerAsync();
+        // Round 3 has empty RetireRewards per config — client ignores rewards at FinalB anyway.
+        await SeedRunAsync(factory, vid, roundId: 3, winCount: 2, battleCount: 3);
+
+        using var client = factory.CreateAuthenticatedClient(vid);
+        var resp = await client.PostAsync("/arena_colosseum/retire", JsonContent.Create(Envelope));
+        Assert.That(resp.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+
+        var body = await resp.Content.ReadAsStringAsync();
+        using var doc = JsonDocument.Parse(body);
+        Assert.That(doc.RootElement.GetProperty("rewards").GetArrayLength(), Is.EqualTo(0),
+            "FinalB retire emits empty rewards per retire.md");
+        Assert.That(doc.RootElement.GetProperty("colosseum_status").GetProperty("now_round_id").GetInt32(),
+            Is.EqualTo(3));
+    }
+}
diff --git a/SVSim.UnitTests/Integration/ArenaColosseumEndToEndTests.cs b/SVSim.UnitTests/Integration/ArenaColosseumEndToEndTests.cs
new file mode 100644
index 00000000..d2bc50d6
--- /dev/null
+++ b/SVSim.UnitTests/Integration/ArenaColosseumEndToEndTests.cs
@@ -0,0 +1,232 @@
+using System.Net;
+using System.Net.Http.Json;
+using System.Text.Json;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.DependencyInjection;
+using SVSim.Database;
+using SVSim.Database.Enums;
+using SVSim.Database.Models;
+using SVSim.UnitTests.Infrastructure;
+
+namespace SVSim.UnitTests.Integration;
+
+/// <summary>
+/// Phase 2 ship gate: a viewer walks the full bracket — entry → register_deck →
+/// (battle_finish × N) → /finish (champion path), plus a separate retire-mid-round
+/// variant. Exercises every Phase 2 endpoint plus Phase 1's /entry + /register_deck.
+/// </summary>
+public class ArenaColosseumEndToEndTests
+{
+    private static readonly object Envelope =
+        new { viewer_id = "0", steam_id = 0, steam_session_ticket = "" };
+
+    private static async Task ConfigureSeasonAsync(SVSimTestFactory factory)
+    {
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+
+        // Season active, free entry allowed (so we don't have to seed currency).
+        var seasonJson = JsonSerializer.Serialize(new
+        {
+            IsColosseumPeriod = true,
+            SeasonId = 100,
+            ColosseumName = "E2E Cup",
+            DeckFormat = (int)Format.Rotation,
+            CrystalCost = 0,
+            RupyCost = 0,
+            TicketCost = 0,
+            IsAllowedFreeEntry = true,
+            FinalRoundEliminateCount = 100,
+        });
+        await UpsertConfigAsync(db, "ColosseumSeason", seasonJson);
+
+        // 3-round bracket. Round 1: BR=2 (clear with 2 wins). Round 2: BR=2. Round 3: BR=2.
+        var roundsJson = JsonSerializer.Serialize(new
+        {
+            Rounds = new[]
+            {
+                BuildRound(1, breakthrough: 2, finishCount: 50),
+                BuildRound(2, breakthrough: 2, finishCount: 100),
+                BuildRound(3, breakthrough: 2, finishCount: 500),
+            },
+            ChampionRewards = new[]
+            {
+                new { Type = (int)UserGoodsType.Crystal, DetailId = 0L, Count = 9999, Name = "E2E Champion" },
+            },
+        });
+        await UpsertConfigAsync(db, "ColosseumRounds", roundsJson);
+    }
+
+    private static object BuildRound(int roundId, int breakthrough, int finishCount) => new
+    {
+        RoundId = roundId,
+        Groups = new[]
+        {
+            new
+            {
+                Group = $"R{roundId}",
+                MaxBattleCount = 5,
+                BreakthroughNumber = breakthrough,
+                EntryNumber = 100,
+            },
+        },
+        FinishRewards = new[]
+        {
+            new
+            {
+                Type = (int)UserGoodsType.Crystal,
+                DetailId = 0L,
+                Count = finishCount,
+                Name = $"R{roundId} finish",
+            },
+        },
+        RetireRewards = new object[]
+        {
+            new
+            {
+                Type = (int)UserGoodsType.Rupy,
+                DetailId = 0L,
+                Count = 10 * roundId,
+                Name = $"R{roundId} retire",
+            },
+        },
+    };
+
+    private static async Task UpsertConfigAsync(SVSimDbContext db, string section, string json)
+    {
+        var existing = await db.GameConfigs.FirstOrDefaultAsync(s => s.SectionName == section);
+        if (existing is null)
+            db.GameConfigs.Add(new GameConfigSection { SectionName = section, ValueJson = json });
+        else
+            existing.ValueJson = json;
+        await db.SaveChangesAsync();
+    }
+
+    private static HttpContent BattleFinishPayload(int battleResult, int isRetire) =>
+        JsonContent.Create(new
+        {
+            battle_result = battleResult,
+            is_retire = isRetire,
+            class_id = 1,
+            total_turn = 5,
+            evolve_count = 1,
+            enemy_evolve_count = 0,
+            recovery_data = "",
+            viewer_id = "0",
+            steam_id = 0,
+            steam_session_ticket = "",
+        });
+
+    private static async Task PromoteRunToRoundAsync(
+        SVSimTestFactory factory, long viewerId, int newRoundId)
+    {
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+        var run = await db.ViewerArenaColosseumRuns.FirstAsync(r => r.ViewerId == viewerId);
+        run.RoundId = newRoundId;
+        run.WinCount = 0;
+        run.LossCount = 0;
+        run.BattleCountThisRound = 0;
+        run.ResultListJson = "[]";
+        // Pull the per-round thresholds for the new round (mirrors what /entry copies on
+        // initial create — Phase 2 doesn't have a real intra-bracket promotion endpoint yet).
+        run.MaxBattleCountThisRound = 5;
+        run.BreakthroughNumberThisRound = 2;
+        await db.SaveChangesAsync();
+    }
+
+    [Test]
+    public async Task Full_three_round_bracket_walk_ends_as_champion()
+    {
+        using var factory = new SVSimTestFactory();
+        await ConfigureSeasonAsync(factory);
+        var vid = await factory.SeedViewerAsync();
+        await factory.SeedDeckAsync(vid, Format.Rotation, number: 1);
+        using var client = factory.CreateAuthenticatedClient(vid);
+
+        // /entry (free)
+        var entryResp = await client.PostAsync("/arena_colosseum/entry",
+            JsonContent.Create(new { consume_item_type = 5, now_round_id = 1, viewer_id = "0", steam_id = 0, steam_session_ticket = "" }));
+        Assert.That(entryResp.StatusCode, Is.EqualTo(HttpStatusCode.OK), "entry must succeed");
+
+        // /register_deck
+        var registerResp = await client.PostAsync("/arena_colosseum/register_deck",
+            JsonContent.Create(new { deck_no_list = "[1]", is_published = true, viewer_id = "0", steam_id = 0, steam_session_ticket = "" }));
+        Assert.That(registerResp.StatusCode, Is.EqualTo(HttpStatusCode.OK), "register_deck must succeed");
+
+        // Round 1: 2 wins → clears breakthrough.
+        for (int i = 0; i < 2; i++)
+        {
+            var r = await client.PostAsync("/colosseum_battle/finish", BattleFinishPayload(battleResult: 1, isRetire: 0));
+            Assert.That(r.StatusCode, Is.EqualTo(HttpStatusCode.OK), $"R1 battle {i} must succeed");
+        }
+        await PromoteRunToRoundAsync(factory, vid, newRoundId: 2);
+
+        // Round 2: 2 wins.
+        for (int i = 0; i < 2; i++)
+        {
+            var r = await client.PostAsync("/colosseum_battle/finish", BattleFinishPayload(battleResult: 1, isRetire: 0));
+            Assert.That(r.StatusCode, Is.EqualTo(HttpStatusCode.OK), $"R2 battle {i} must succeed");
+        }
+        await PromoteRunToRoundAsync(factory, vid, newRoundId: 3);
+
+        // Round 3: 2 wins → champion path on /finish.
+        for (int i = 0; i < 2; i++)
+        {
+            var r = await client.PostAsync("/colosseum_battle/finish", BattleFinishPayload(battleResult: 1, isRetire: 0));
+            Assert.That(r.StatusCode, Is.EqualTo(HttpStatusCode.OK), $"R3 battle {i} must succeed");
+        }
+
+        // /arena_colosseum/finish (champion path)
+        var finishResp = await client.PostAsync("/arena_colosseum/finish", JsonContent.Create(Envelope));
+        Assert.That(finishResp.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+
+        var body = await finishResp.Content.ReadAsStringAsync();
+        using var doc = JsonDocument.Parse(body);
+        var root = doc.RootElement;
+        Assert.That(root.GetProperty("colosseum_status").GetProperty("is_champion").GetBoolean(), Is.True);
+        // Final R3 finish reward + champion bundle = 2 entries.
+        Assert.That(root.GetProperty("reward_list").GetArrayLength(), Is.EqualTo(2));
+
+        using var verifyScope = factory.Services.CreateScope();
+        var db = verifyScope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+        var run = await db.ViewerArenaColosseumRuns.FirstOrDefaultAsync(r => r.ViewerId == vid);
+        Assert.That(run, Is.Null, "champion run must be deleted on /finish");
+    }
+
+    [Test]
+    public async Task Retire_during_round_2_emits_round_capped_consolation()
+    {
+        using var factory = new SVSimTestFactory();
+        await ConfigureSeasonAsync(factory);
+        var vid = await factory.SeedViewerAsync();
+        await factory.SeedDeckAsync(vid, Format.Rotation, number: 1);
+        using var client = factory.CreateAuthenticatedClient(vid);
+
+        // entry + register_deck + clear R1 + promote
+        await client.PostAsync("/arena_colosseum/entry",
+            JsonContent.Create(new { consume_item_type = 5, now_round_id = 1, viewer_id = "0", steam_id = 0, steam_session_ticket = "" }));
+        await client.PostAsync("/arena_colosseum/register_deck",
+            JsonContent.Create(new { deck_no_list = "[1]", is_published = false, viewer_id = "0", steam_id = 0, steam_session_ticket = "" }));
+        for (int i = 0; i < 2; i++)
+            await client.PostAsync("/colosseum_battle/finish", BattleFinishPayload(battleResult: 1, isRetire: 0));
+        await PromoteRunToRoundAsync(factory, vid, newRoundId: 2);
+
+        // One mid-round battle, then retire.
+        await client.PostAsync("/colosseum_battle/finish", BattleFinishPayload(battleResult: 2, isRetire: 0));
+
+        var retireResp = await client.PostAsync("/arena_colosseum/retire", JsonContent.Create(Envelope));
+        Assert.That(retireResp.StatusCode, Is.EqualTo(HttpStatusCode.OK));
+
+        var body = await retireResp.Content.ReadAsStringAsync();
+        using var doc = JsonDocument.Parse(body);
+        var rewards = doc.RootElement.GetProperty("rewards");
+        Assert.That(rewards.GetArrayLength(), Is.EqualTo(1));
+        Assert.That(rewards[0].GetProperty("name").GetString(), Is.EqualTo("R2 retire"),
+            "retire payload must reflect the round the viewer was IN, not their starting round");
+
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+        Assert.That(await db.ViewerArenaColosseumRuns.AnyAsync(r => r.ViewerId == vid), Is.False);
+    }
+}
diff --git a/SVSim.UnitTests/Services/ArenaColosseum/ColosseumProgressionServiceTests.cs b/SVSim.UnitTests/Services/ArenaColosseum/ColosseumProgressionServiceTests.cs
new file mode 100644
index 00000000..9158c651
--- /dev/null
+++ b/SVSim.UnitTests/Services/ArenaColosseum/ColosseumProgressionServiceTests.cs
@@ -0,0 +1,181 @@
+using NUnit.Framework;
+using SVSim.Database.Enums;
+using SVSim.Database.Models;
+using SVSim.Database.Models.Config;
+using SVSim.EmulatedEntrypoint.Services.ArenaColosseum;
+
+namespace SVSim.UnitTests.Services.ArenaColosseum;
+
+/// <summary>
+/// Pure-logic tests for the bracket-advancement / promotion / reward-bundle service.
+/// No DB, no controllers, no HTTP — these are the only place to lock the spec README's
+/// "&lt; FinalB" cap rule + the 3008 promotion trigger semantics.
+/// </summary>
+[TestFixture]
+public class ColosseumProgressionServiceTests
+{
+    private static ColosseumRoundsConfig BuildThreeRoundConfig() => new()
+    {
+        Rounds = new()
+        {
+            new ColosseumRoundsConfig.RoundEntry
+            {
+                RoundId = 1,
+                Groups = new() { new() { Group = "", MaxBattleCount = 5, BreakthroughNumber = 3, EntryNumber = 100_000 } },
+                FinishRewards = new()
+                {
+                    new() { Type = UserGoodsType.Crystal, DetailId = 0, Count = 100, Name = "Round 1 bonus" },
+                },
+                RetireRewards = new()
+                {
+                    new() { Type = UserGoodsType.Rupy, DetailId = 0, Count = 50, Name = "Consolation" },
+                },
+            },
+            new ColosseumRoundsConfig.RoundEntry
+            {
+                RoundId = 2,
+                Groups = new() { new() { Group = "Group A", MaxBattleCount = 5, BreakthroughNumber = 4, EntryNumber = 10_000 } },
+                FinishRewards = new()
+                {
+                    new() { Type = UserGoodsType.Crystal, DetailId = 0, Count = 250, Name = "Round 2 bonus" },
+                },
+            },
+            new ColosseumRoundsConfig.RoundEntry
+            {
+                RoundId = 3,
+                Groups = new() { new() { Group = "Final", MaxBattleCount = 5, BreakthroughNumber = 4, EntryNumber = 1_000 } },
+                FinishRewards = new()
+                {
+                    new() { Type = UserGoodsType.Crystal, DetailId = 0, Count = 1000, Name = "Final clear" },
+                },
+            },
+        },
+        ChampionRewards = new()
+        {
+            new() { Type = UserGoodsType.Item, DetailId = 5, Count = 1, Name = "Champion Pack" },
+        },
+    };
+
+    [Test]
+    public void Win_threshold_advances_round_1_to_round_2()
+    {
+        var svc = new ColosseumProgressionService();
+        var rounds = BuildThreeRoundConfig();
+        var run = new ViewerArenaColosseumRun { RoundId = 1, WinCount = 3, BattleCountThisRound = 3 };
+
+        var decision = svc.DecideAdvancement(run, rounds);
+
+        Assert.That(decision.NextRoundId, Is.EqualTo(2));
+        Assert.That(decision.IsBracketEnd, Is.False);
+        Assert.That(decision.IsChampion, Is.False);
+    }
+
+    [Test]
+    public void Loss_cap_ends_bracket_at_current_round()
+    {
+        var svc = new ColosseumProgressionService();
+        var rounds = BuildThreeRoundConfig();
+        var run = new ViewerArenaColosseumRun
+        {
+            RoundId = 2,
+            WinCount = 3, // one short of breakthrough (4)
+            BattleCountThisRound = 5, // hit the cap
+            LossCount = 2,
+        };
+
+        var decision = svc.DecideAdvancement(run, rounds);
+
+        Assert.That(decision.NextRoundId, Is.EqualTo(2));
+        Assert.That(decision.IsBracketEnd, Is.True);
+        Assert.That(decision.IsChampion, Is.False);
+    }
+
+    [Test]
+    public void Final_round_breakthrough_marks_champion()
+    {
+        var svc = new ColosseumProgressionService();
+        var rounds = BuildThreeRoundConfig();
+        var run = new ViewerArenaColosseumRun
+        {
+            RoundId = 3,
+            WinCount = 4, // hit breakthrough on the final round
+            BattleCountThisRound = 4,
+        };
+
+        var decision = svc.DecideAdvancement(run, rounds);
+
+        Assert.That(decision.NextRoundId, Is.EqualTo(3));
+        Assert.That(decision.IsBracketEnd, Is.True);
+        Assert.That(decision.IsChampion, Is.True);
+    }
+
+    [Test]
+    public void ShouldPromoteToRankMatching_flips_once_on_3008()
+    {
+        var svc = new ColosseumProgressionService();
+        var run = new ViewerArenaColosseumRun { IsRankMatching = false };
+
+        Assert.That(svc.ShouldPromoteToRankMatching(run, 3004), Is.False,
+            "3004 SUCCEEDED is not the promotion signal");
+        Assert.That(svc.ShouldPromoteToRankMatching(run, 3008), Is.True,
+            "3008 is the colosseum-specific promotion trigger per do-matching.md");
+
+        run.IsRankMatching = true;
+        Assert.That(svc.ShouldPromoteToRankMatching(run, 3008), Is.False,
+            "already promoted — no second flip");
+    }
+
+    [Test]
+    public void BuildRetireRewards_returns_round_specific_bundle()
+    {
+        var svc = new ColosseumProgressionService();
+        var rounds = BuildThreeRoundConfig();
+        var run = new ViewerArenaColosseumRun { RoundId = 1 };
+
+        var rewards = svc.BuildRetireRewards(run, rounds);
+
+        Assert.That(rewards.Count, Is.EqualTo(1));
+        Assert.That(rewards[0].Type, Is.EqualTo(UserGoodsType.Rupy));
+        Assert.That(rewards[0].Count, Is.EqualTo(50));
+    }
+
+    [Test]
+    public void BuildRetireRewards_returns_empty_when_round_has_none()
+    {
+        var svc = new ColosseumProgressionService();
+        var rounds = BuildThreeRoundConfig();
+        // Round 2 has no RetireRewards configured — server still emits an empty list per spec.
+        var run = new ViewerArenaColosseumRun { RoundId = 2 };
+
+        var rewards = svc.BuildRetireRewards(run, rounds);
+
+        Assert.That(rewards, Is.Empty);
+    }
+
+    [Test]
+    public void BuildFinishRewards_appends_champion_bundle_when_champion()
+    {
+        var svc = new ColosseumProgressionService();
+        var rounds = BuildThreeRoundConfig();
+        var run = new ViewerArenaColosseumRun { RoundId = 3, IsChampion = true };
+
+        var rewards = svc.BuildFinishRewards(run, rounds);
+
+        Assert.That(rewards.Count, Is.EqualTo(2), "round 3 finish + champion bundle");
+        Assert.That(rewards.Any(r => r.Name == "Final clear"), Is.True);
+        Assert.That(rewards.Any(r => r.Name == "Champion Pack"), Is.True);
+    }
+
+    [Test]
+    public void BuildFinishRewards_omits_champion_bundle_when_not_champion()
+    {
+        var svc = new ColosseumProgressionService();
+        var rounds = BuildThreeRoundConfig();
+        var run = new ViewerArenaColosseumRun { RoundId = 1, IsChampion = false };
+
+        var rewards = svc.BuildFinishRewards(run, rounds);
+
+        Assert.That(rewards.Count, Is.EqualTo(1));
+        Assert.That(rewards[0].Name, Is.EqualTo("Round 1 bonus"));
+    }
+}