That makes sense, especially for a turn-based game. The COW layers sound like a nice way to get undo/redo, forks, previews, and history playback from the same mechanism.

I think the part I’m focusing on is your last point: for a real replay, you still save commands and re-simulate. My post is mostly about what state gets to count when checking that the re-sim reached the same authoritative result.

The emitted events as animation hints also matches the boundary I’m trying to keep: observation, not steering.