try english opening you can play it against almost anything!!! (I learned it from top chess)
killer King Achievement

With a variant of chess maybe.
You can NEVER get killer king with variant. You have to get it in NORMAL CHESS

It is never possible to checkmate with a king because that would put your king in check.
You have discovery mate though

just got killer king, on a rated game, my opponent was basically free! he gave away his queen, then his rooks, horses, and pawns. then i got him in a position for a mate with rook, but instead, decided to move my king up to start the discovered attack, and pushed rook up, moved king down, and checkmate!!!

[Event "?"]
[Site "Chess.com iPhone"]
[Date "2024.05.27"]
[Round "?"]
[White "iwonaviper"]
[Black "CR1MS0N4RM4D1LL0"]
[Result "0-1"]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
[WhiteElo "476"]
[BlackElo "512"]
1. e4 e5 2. Nf3 Bc5 3. c3 Qf6 4. b4 Bb6 5. d4 exd4 6. cxd4 Nc6 7. Bb2 Nxb4 8. Bc3 Nc6 9. Na3 Nh6 10. Rc1 Ng4 11. h3 Bxd4 12. Bxd4 Nxd4 13. Nxd4 Nxf2 14. Rg1 Nxd1 15. Rxd1 d5 16. exd5 Qe5+ 17. Be2 g5 18. Nc4 Qe7 19. Nf5 Bxf5 20. g4 Bc8 21. Rf1 h5 22. gxh5 g4 23. hxg4 Bxg4 24. Rd2 Rxh5 25. Rf4 Rh4 26. Kd1 f5 27. Na3 Rh1+ 28. Kc2 Qc5+ 29. Kb2 Qc1+ 30. Kb3 Bxe2 31. Rxe2+ Kd8 32. Rxf5 Rh3+ 33. Ka4 b6 34. Rf8+ Kd7 35. Rxa8 b5+ 36. Kxb5 Rh5 37. Nc4 c6+ 38. Kc5 Rxd5+ 39. Kb4 c5+ 40. Ka5 Qxc4 41. Rxa7+ Kd6 42. Ra6+ Kc7 43. Ra7+ Kc6 44. Re6+ Rd6 45. Re8 Qb4+ 46. Ka6 Kd5# {0-1}

Thank you for understanding☺️
AND DONT REPEAT THAT EVER AGAIN
jesus man calm down, sometimes a call it a horse because it is a horse- and tot eh other guy that said that my chess rating is the same as my iq, thank you mate, i guess i hate 300+ iq

calm down man, i know about chess notation, its just a habit of mine that i sometimes call a knight a horse. but essus dude, you don't have to threaten me, plus what was the "your iq is the same as your ELO"? thats a compliment, then my iq would be 300+. please don't harass me, i was just celebrating that i checkmated someone with a king :(

Why you should never try the killer king achievement:
https://www.chess.com/analysis/game/live/115297736713?tab=review

I do not know how
Please tell me
Discovered Check . GO to my blog - https://www.chess.com/blog/BirdLikeChess/how-to-get-killer-king

Thank you for understanding☺️
AND DONT REPEAT THAT EVER AGAIN
Bro what are you yapping about?
as an Indian (chess was created in India) We have always called it a horse. Even in the ancient language it was called a horse. Its the Colonizers who called them "Knight".
I was planning to play the english opening (my favorite opening) but it turned out to be the king pawn opening the whale variation