Here's a selfmate problem that just might be baffle you! Thus, I name it "Tricky Tricky!"
It's White to move and selfmate themselves in 8 moves.
Can you find the secret?
As always, no computers and only your own brain! Good luck solving!
I think I've figured it out.
2.a8=Q pawn move
3.e8=Q pawn move
4.Qe1 pawn move
5.Qf8 pawn move
Does that look right?
As per requested by @Dorian Fusco, here is what my original solution was before. @BoredAtWork, amazingly, and to my surprise, found an alternate way! Congratulations to them!
My Original Solution:
1. Bh5+ Rg4 2. e8=Q Any Pawn Move 3. a8=Q Any Pawn Move 4. Qa1 Any Pawn Move 5. Qc1 Any Pawn Move 6. Qc2! bxc2 7. Qe1 ...7. c1=Q 8. Qd1+ Qxd1# or Qe3+ Qxe3# ...7. c1=N 8. Qe2+ Nxe2# ...7. c1=R 8. Qd1+ Rxd1# ...7. c1=B 8. Qe3+ Rxe3#
Now do you see why I considered this to be a tricky question? ;D
I've looked at this problem for so long that I begin to think perhaps the composer made a slight error in the composition. So I think it would be smart to ask the composer if my try is what he had in mind before I continue cracking my brain. My try is as follows: 1.Bh5+ Rg4 Then the next 4 black pawn moves are forced (irrespective of the order in which they are played. Thus I'll just give next 4 white moves). 2.a8=Q ... 3.Qg8 ... 4.e8=R ... 5.Re1 ... (Notice now that black has exhausted all his pawn moves and in fact would have been stalemate if it was black's turn now. However, it's white's turn.) The solution continues 6.Qg5 hxg5(only move) 7.Re2 gxf4(only move) 8.Rd2 fxg3+ (This is where I thought perhaps the composer missed that 8.fxg3+ is not a mate as White can play the only move, 9.Bxg4+). I feel it is easy for the composer to miss this. Pls can you confirm that it is not a mistake on your part so I can get back to cracking my brain on it again.
very partial answer - first two steps
1. Bh5+ Rg4
2. a8=Q d6