Black to move
It was a blunder, objectively speaking, that put a black pawn on g3. Black staked the whole game on setting up a checkmate that White could have stopped fairly easily. But White greedily grabbed first a pawn that was en prise, then grabbed with his own cleric the bishop that had taken the knight on f3. Now it's Black's move and checkmate in seven.
Chess Tactics Training Day #1 (11-28-15)
37 minutes ago