diff --git a/SVSim.BattleNode/Sessions/BattleSession.cs b/SVSim.BattleNode/Sessions/BattleSession.cs
index e7ae2b0..a6b5dd6 100644
--- a/SVSim.BattleNode/Sessions/BattleSession.cs
+++ b/SVSim.BattleNode/Sessions/BattleSession.cs
@@ -1,3 +1,4 @@
+using System.Net.WebSockets;
 using Microsoft.Extensions.Logging;
 using SVSim.BattleNode.Protocol;
 using SVSim.BattleNode.Sessions.Dispatch;
@@ -125,20 +126,34 @@ public sealed class BattleSession
 
             cts.Cancel(); // unblock the survivor's RunAsync read loop
             try { await Task.WhenAll(aTask, bTask).ConfigureAwait(false); }
-            catch { /* swallow cancellation / WS exceptions */ }
+            catch (Exception ex) when (ex is OperationCanceledException or WebSocketException) { }
+            catch (AggregateException ex) when (ex.Flatten().InnerExceptions.All(
+                e => e is OperationCanceledException or WebSocketException)) { }
+            catch (Exception ex)
+            {
+                _log.LogWarning(ex, "BattleSession {Bid}: unexpected exception from WhenAll (PvP drain)", BattleId);
+            }
         }
         else
         {
             // Bot mode: the NoOp opponent's RunAsync returns immediately; wait for the real
             // participant. The session keeps running for the real one.
             try { await Task.WhenAll(aTask, bTask).ConfigureAwait(false); }
-            catch { /* swallow */ }
+            catch (Exception ex) when (ex is OperationCanceledException or WebSocketException) { }
+            catch (AggregateException ex) when (ex.Flatten().InnerExceptions.All(
+                e => e is OperationCanceledException or WebSocketException)) { }
+            catch (Exception ex)
+            {
+                _log.LogWarning(ex, "BattleSession {Bid}: unexpected exception from WhenAll (Bot drain)", BattleId);
+            }
         }
 
-        // Audit Md11 — release per-participant outbound archives at battle-end
-        // (only RealParticipant has one; bots don't archive). Heavy state is
-        // dropped synchronously here so the participant's TerminateAsync doesn't
-        // need to keep the dict alive through its disposal handshake.
+        // Unsubscribe event handlers so the session + state aren't pinned by live delegates.
+        A.FrameEmitted -= OnFrameFromA;
+        B.FrameEmitted -= OnFrameFromB;
+
+        // Release per-participant outbound archives at battle-end
+        // (only RealParticipant has one; bots don't archive).
         if (A is RealParticipant rpA) rpA.Outbound.Clear();
         if (B is RealParticipant rpB) rpB.Outbound.Clear();
 
@@ -146,6 +161,10 @@ public sealed class BattleSession
             A.TerminateAsync(BattleFinishReason.NormalFinish),
             B.TerminateAsync(BattleFinishReason.NormalFinish))
             .ConfigureAwait(false);
+
+        await A.DisposeAsync().ConfigureAwait(false);
+        await B.DisposeAsync().ConfigureAwait(false);
+        _dispatchGate.Dispose();
     }
 
     private Task OnFrameFromA(MsgEnvelope env, CancellationToken ct) => HandleFrameAsync(A, env, ct);