Chess puzzle (Checkmate)
Moves: 1. d4 Nf6 2. Nf3 c5 3. d5 b5 4. Bg5 Qb6 5. Bxf6 Qxf6 6. c3 Qb6 7. e4 d6 8. a4
b4 9. Nbd2 bxc3 10. bxc3 Ba6 11. Rb1 Qa5 12. Bxa6 Qxa6 13. Qe2 Qxe2+ 14. Kxe2
g6 15. Rb7 Bg7 16. Rhb1 Nd7 17. Nc4 Bxc3 18. a5 Bf6 19. a6 Nb6 20. R1xb6 axb6
21. Nxb6 Rxa6 *
Position (FEN): 4k2r/1R2pp1p/rN1p1bp1/2pP4/4P3/5N2/4KPPP/8 w k - 0 22
White to move.
Themes:  Endgame Mate in 1 
Puzzle rating: 534
Best move: Rb8#