If you found this move, you can reach 2000+!
Line 1. 1. g3+ Kh3
2. Qf5+ Ng4
3. Qh5 mate
Line 2. 1. g3+ Kh5
2. Qf5+ g5
3. g4+ Kh4
4. Kg2 (Rh1 mate next) Qd5+
5. f3 and Rh1 mate
Line 3. 1. g3+ Kg4
2. Kg2 Qd5+
3. f3+ Kg5
4. Be3+ Kh5
5. Rh1 mate
Line 1. 1. g3+ Kh3
2. Qf5+ Ng4
3. Qh5 mate
Line 2. 1. g3+ Kh5
2. Qf5+ g5
3. g4+ Kh4
4. Kg2 (Rh1 mate next) Qd5+
5. f3 and Rh1 mate
Line 3. 1. g3+ Kg4
2. Kg2 Qd5+
3. f3+ Kg5
4. Be3+ Kh5
5. Rh1 mate
What about Kg5
If 1….Kg5, then
2. Be3+ Kh5
3. Qf5+ g5
4. g4+ Kh4
5. Kg2 Qd5+ (Rh1 mate next)
6. Qf3 Qxf3+
7. Kxf3 (Rh1 mate next) Nxg4
8. Rh1+ Nh2
9. Rxh2 mate
If 1….Kg5, then
2. Be3+ Kh5
3. Qf5+ g5
4. g4+ Kh4
5. Kg2 Qd5+ (Rh1 mate next)
6. Qf3 Qxf3+
7. Kxf3 (Rh1 mate next) Nxg4
8. Rh1+ Nh2
9. Rxh2 mate
It has to be Mate is 7 though, right?
I won't give away the answer, but I don't like approaching this position as a "mate in 7" because the engine will reach mate in 7 by throwing away material in a engine-like way; I also don't like this because the intuitive candidate moves of g3+ and Qf5 are both overwhelmingly good for white.
It was a good exercise in calculation though; I'd approach this from that perspective, or from the mindset of this being a mating net (as it appears to be even without knowing it was mate in 7 with computer best defense).
I would play Re5 here. Creating the mating net, cutting off the king's escape squares - threatening Qh3#.
Black is forced to play ...QxR. White can play the intermezzo Qh3+. Black is forced to play ...Kg5, to which White responds by capturing Black's queen with BxQ.
That's as far as I looked, because that position is completely winning for White, so it would just be a matter of finding the mate from there (my visualization abilities pretty much end at this point, so I'd just wing it from there on out).
Hey Friends!
Let me see if you can find the moves. It's mate in 7
White to Play!