The last move of the game? en passent mate, google it.
illegal moves

I suggest you read this:
https://www.chess.com/blog/VladimirHerceg91/using-en-passant-to-gain-a-mental-advantage
Your opponent is just using @vladimirherceg91 's method of gaining a mental/psychological advantage
Hi, has anyone ever came accross an illegal move? This is the second time its happened to me and I'm not sure whats going on. Is it a bug in the chess engine?
https://www.chess.com/daily/game/160380736