So I bought https://store.steampowered.com/app/1349230/5D_Chess_With_Multiverse_Time_Travel/ based on the strength of the name alone, but the intro video also sold me? It's chess, but in addition to moving on the board you can move backwards or sideways in time -- no pure forward because an objective external history exists but the game is non-deterministic, so the closest you get to "forward" is "to an established alternate timeline that's already further ahead on the global clock than this board's current" -- which creates alternate timelines, and you can take your turn on any "present" board. Check can be escaped by sending a king into the past, or by capturing attackers using pieces from alternate timelines. I just won a game by moving a queen to mate in the past with no pieces in any alternate timeline available to block or capture. Even though the king could escape in the present, my next move would have been to send my queen back in time, the king's fate inexorably sealed.

10/10. No notes.