# Something Simple

A simple task: It’s White to move selfmate themselves in three moves. White pawns are moving up.

• So is black trying to make the "worst" moves in order to thwart us? Also, I'm unconvinced that enigmatic-puzzle is a good tag here. Sep 7, 2019 at 14:44
• Is it an enigmatic puzzle because ROT13(gur tbny vf gb cebir gung vg'f vzcbffvoyr)? Sep 9, 2019 at 21:37
• Can we promote to enemy pieces? This was once legal but is no longer legal. Sep 11, 2019 at 16:56
• @RewanDemontay Cebzbgvat gb rarzl cvrprf sryg yvxr gur bayl ravtzngvp lrg fbzrjung yrtvgvzngr guvat bar pbhyq qb gb npuvrir fryszngr. V'yy gel naq svaq n fbyhgvba abj. Sep 11, 2019 at 19:33
• Accepted solution contains an illegal move. Downvoting... Sep 12, 2019 at 17:58

The secret is that we are

allowing promotion to an enemy piece. A literal reading of a previous version of the promotion rule implied that promotion to an enemy piece was legal. See this question: https://chess.stackexchange.com/questions/2756/do-the-official-rules-of-chess-forbid-promoting-a-pawn-to-a-piece-of-the-opposit

As a result, we could

selfmate in two moves, as follows:  1. dxc8=bN+ Nd6 2. h8=bN Ng7#  where the "b" prefix indicates that we are promoting to black knights in both cases.

However, the puzzle asks us to

selfmate in 3 moves instead. The only way to do so is to throw in an in-between move:  1. dxc8=bN+ Nd6 2. b8=bN+ Nc6 3. h8=bN Ng6#  All moves are forced.