I'm wondering what "rarest" means. Is it a checkmate that has occurred only once or one that has never occurred.
What's the rarest kind of checkmate?


Castle checkmate, ofc the rarest
I did it! https://www.chess.com/game/live/132392984887

In no particular order, here's (arguably) the top ten:
1. En Passant
2. O-O/O-O-O (I'd say O-O is rarer)
3. Double-disambiguated move
4. King move
5. Promoting to a knight
6. Double check (this one's probably debatable)
7. "Insufficient" material (that is, rare scenarios where a lone knight or bishop can do the job)
8. King and one pawn
9. Literal forced checkmate (that is, a situation checkmate is the only legal move)
10. Tournament play checkmate (players virtually always resign)
what I didtn see at all..its a mate with en-passant move!