Forcing the bishop to a decision. Either he takes my knight, and I end up with the bishop pair and an open f-file, or he backs up, and I still end up with the open f-file.

It was here that I realized how completely and utterly trapped his knight was. I could actually completely disregard it, because the only way it could get anywhere was via g1-e2-c1 and threaten my bishop, but even then he would have to trade it, and I would have a passed pawn on the sixth rank, enough compensation for losing the bishop pair. But here, he had to defend the pawn. My queen had successfully negotiated to the open f-file, and he had no defense left. Checkmate is now only a delayed inevitability. Qe1 or Qf1 are the best possibilities for White to just barely hold, but even then I would still play Qf3 and the knight would be wholly lost. My DS bishop would join in the fun soon enough via the e5 square.

I cannot give this move a ? or a ?? because there was not much he could do in defense of his knight, his pawns, etc, etc, but this move only sped up his demise a considerable bit. Qf3 would now come with check, and the knight would now certainly be lost after Kg1 followed by Qxe2. Bxe2 could also be fine, but it is better to not delay too long by letting White have counterplay with Qd8+ and Black's King gets a couple of checks and a bit flustered. Too much trouble with little result.

?? The move that leads to the quickest demise, a mate in 1 since the knight is pinned.