During Christmas holidays I tend to indulge in online chess playing a bit too much, wasting several hours a day that could be used to get back on track with the gazillion research projects I am currently trying to keep pushing. But at times it gives me pleasure, when I conceive some good tactical sequence. 
Take the position below, from a 5' game on chess.com today. White has obtained a winning position, but can you win it with the clock ticking? (I have less than two minutes left for the rest of the game...)


In the diagram White is to move, after black blundered in a more or less even position by playing Qb4-d6, thinking that with his move he would take advantage of my pinned Ne5. Unfortunately for him, this opens the way to a pretty sequence. Please find the full variation leading to a completely winning position. Extra points if you do it without moving pieces on the board and in less than 30 seconds!




I will post the solution below tomorrow... If you need a hint, the poor position of the Nb8 is part of the problem that black is facing. 

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Solution:

First, note that white could not play 1.Nc6?, hoping in 1...Qxg3? 2.Ne7+ winning an exchange, as black would instead reply with 1....Rxe2 (threatening Rxe1 mate) 2.Rxe2 Rxe2 3.Nxe2 Qxg3 followed by Nxc6, winning.
Instead, white simply plays 1.Ne4! and black can't take the knight on e5 as 1....Qxe5?? would result in 2.Nxf6+! Qxf6 3. Rxe7, when the undefended Nb8 prevents a recapture with the Re8.
On the other hand, the queen cannot move away from the defense of the Bf6, as white is threatening Nxf6+ which is also forking the Re8, as the g7 pawn is pinned. Black's only remaining option, which he played, is 1....Qe6. However this allows the following sequence: 2.Nxf6+, Qxf6, 3.Ng4!! and black is lost: 3....R:e2 allows 4.Nxf6+, so black must defend the Re7 with the queen. This can only be accomplished by 3...Qg5, which is what was played in the game. But now, 4.Rxe7 wins, as 4....Rxe7 meets with 5.Qxb8+ (the poor undefended knight is indeed the culprit of black's demise) and white mates.

Not a difficult combination altogether, but there are a few variations to check, and in a blitz game such tactics can be easily overlooked. Am proud of myself for finding it today!