
Visualization Puzzles
If you can't visualize a changing position, you will never be a good player, no matter what you consider a "good player" to be.
Easy:
If 7. d5 Na5 8. Qa4 c5, does 9. Qxa5 work?
Medium:
After 12...Nfxe4 13. Nxe4 Bxd4 14. Bg5 f6 find the win for White
Difficult:
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. f3 0-0 5. a3 Be7 6. d5 exd5 7. cxd5 Re8 8. e4 Bc5 9. Nge2 d6 10. Bg5 h6 11. Bf4 c6 12. Qd2 cxd5 13. Nxd5 Nxd5 14. Qxd5 Nc6 15. Nc3 Nd4 16. Rd1 Be6 17. Qxb7 Rb8 18. Qa6 Rxb2 19. Na4
Do not use a board for these moves. If you do, then this is not difficult. Black to play, find the mate in 2.