We are just back from the final round of the Slovak Extraliga. My wife (milacik(IM) here on Chess Tempo) played a fantastically deep combination to win her game against the very experienced Grandmaster Lubomir Ftacnik, who has been ranked in the top 100 in the world in the past.
Here is the position at the beginning of the combination.

Black has just played f3 attacking the White rook on e2. Black has a very nice position up a pawn. I had already written this off as a loss for us, and went back to my game. My wife sets a devious trap and had seen all the way to the mate on move 13!
1.Re4
Doesn't this just hang the pawn on b2 to 1..Nxb2, when Black is up two pawns and attacking the White rook on d1? The Grandmaster calculates a long time, thinks he sees the trap, and thinks he has seen farther and has a way out of the trap:
1... Nxb2??
Loses the game by force. He had to play 1...d5, and Black is clearly better then. But he got a little greedy and took that second pawn.
2.Nh6+ Kh8
3.Rd2
This is the supposed trap... the knight has no where to go. But the GM thinks he has seen a little farther and plays
3... Qc6
This attacks the White rook on e4 and at the same time provides an escape for the knight at a4.
4.Rh4 Na4

5.Qc2
A devious move, threatening to take the knight on a4, and threatening Nf7+ Rxf7 Qxh7#. But GM Ftacnik had seen all of this when he played 1...Nxb2, and plays
5... Bxc3
Now the GM was looking fairly proud of himself! He has protected against the mate (Nf7+ Rxf7 will protect h7, and the knight on a4 can't be taken because the White rook on d2 is hanging. And he is three pawns up! He had seen all this when he played 1...Nxb2.
But my wife had seen ALL of this and much more before she played 1.Re4! She now played
6.Rd3
If the bishop moves, the knight will hang. Of course Black could now play a move such as 6...Ba1, giving away the knight on a4, but analysis later showed that inspite of his 3 pawns he is losing. Instead, the GM instantly played
6... Bd4

which protects the bishop and blocks the rook on h4 from attacking the knight on a4. This was as far as Ftacnik had seen when he first played 1...Nxb2 and now he was happy with his three extra pawns and all the hanging pieces and mates are covered. At least he thought so! But now come the final shocking blows:
7.Rdxd4!
This part of the combination is not so difficult to see. But to plan this 6 moves earlier shows amazing talent.
7... cxd4
8.Nf7+!!
What, just hanging the knight? No!
8... Rxf7
9.Bf6+
One shock after another.
9... Kg8
10.Qg6+!

Boom! A big crowd had gathered around the game watching the upset! Ftacnik had to resign because of 10...hxg6 11.Rh8# mating with the only two pieces White has left, or 10...Kf8 11.Qh6+ Kg8 12.Rg4+ Rg7 13.Qxg7#
An amazingly deep combination. My wife had seen all the way to 13.Qxg7+ when she played 1.Re4. That's 25-ply in computer speak. There's a reason she plays board 2 on our team, ahead of two Grandmasters on boards 3 and 4! She has the tactical ability of a 2700 GM, and just needs to work on her openings and positional play.