- sleep_op_0xc8 @0x420ec0: arms a non-blocking main-loop-polled timer (sleep_timer_arm @0x44cff0); operand = milliseconds. Also carries anti-tamper + gfx cmd-type 3 (not needed host-side). - 0x20c = gfx_op_0x20c_present_frame (host presents continuously -> noop_headless). - Ghidra annotated + saved; opcodes.toml rebuilt (lint clean); engine-re.md. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>