Tactical Failure

My second game in the 2013 Collyer Memorial chess tournament was a series of missed opportunities. I built up a strong position, and failed to deliver the knockout blow. In the end, my opponent blundered in time pressure in a drawn ending (that it was a draw was not clear to us, but is confirmed by the six-piece tablebases).

Perhaps my readers can do better than I did in a series of critical positions. In each of the positions below, I played a suboptimal move.

White to move

White to move

White to move 

White to move

I stopped recording the game when my opponent and I were both down to two minutes. We reached this position.

Black to move

My opponent made the worst possible move.