I came up with a great chess variant ages ago, and finally got around to making a computer version of it last week.
Implied Chess:
Rule 1: Chess
Rule 2: You can't capture normally
Rule 3: Any piece threatened by two enemy pieces is captured (except kings)
Rule 4: The player who just moved captures first
Rule 5: No En Passant (it just doesn't make sense)
Rule 6: Check and checkmate are normal
That's quite fun (especially chain-capturing!), can't beat Alpha Beta 3 yet. Any reasons for Rule 6?
Thanks!
Check and checkmate are normal because it's just way too hard to checkmate the king with dual threats.
I can't beat Alpha Beta 3 yet either. If anyone starts beating 4 I'll put some effort into optimizing the search so it can go deeper. Going 10 ply deep is pretty standard for a chess engine, so it's pretty embarrassing for humanity that nobody is beating the 3-ply setting. I think this game actually favors computers over humans more than regular chess does.
I scooped up a handful of Knightmare Chess decks when I saw 'em really cheap. Still haven't tried, but the idea of a chess variant with physical cards that Do Things to the game, sounded very interesting
https://en.wikipedia.org/wiki/Knightmare_Chess