I think the trick is to keep the king trapped and to avoid stalemate. Hmm...
Mate in 6. Masters only! :D

This adds a whole new meaning to the phrase "forced mate."
+1
I calculated every single variation. 1. d4!! (Kb8?? Kb7!!! Kc8! Kxc8 0-1) (d2 Kb7! d1=Q Kxa8 0-1) (axa4!? b5! axb5 stalemate!(a5 b4 a6 b3 ab6 b2 b5 b1=Q 0-1) b5?? (b-a5!! was very strong leading to stalemate after white has avoiding all the pitfalls of move 1) d5! (d-c5 was also strong) b4?? (again b-a5 is stalemate) axb4! (d-c6 is also winning) a3 b5! (d-c6 was still strong, but not as fast) a2 (a-b3 (a-b2?? b7#!!) b6 b2 b7#) b6 a1=Q (b1=N b7#, or b1=Q?? b8=Q+!!!!(exclam!) Qxb8 axb8#) b7#!! It was tough working through all the variations but it was totally worth it.
This puzzle was the first puzzle of the Australian junior solving championship. However, some people still did not solve it!

Was just working some endgames on ChessMentor and thought I'd give this one a try. Got it on the first attempt in about 1:30...quite surprisingly.
That lesson I just took on opposition paid off already.

Can somebody please tell me the answer? I'm not sure, I may have to send out Stockfish to help me...

Can somebody please tell me the answer? I'm not sure, I may have to send out Stockfish to help me...
Are you serious? Just keep clicking the little bulb under the puzzle and it will show you the correct moves.
You're an 1822 bullet. You bullet guys are supposed to be great at tactics. You should have nailed this endgame one.

Can somebody please tell me the answer? I'm not sure, I may have to send out Stockfish to help me...
Are you serious? Just keep clicking the little bulb under the puzzle and it will show you the correct moves.
You're an 1822 bullet. You bullet guys are supposed to be great at tactics. You should have nailed this endgame one.
Ever heard of the word 'joking'?
And seriously, do you know that the puzzle is a forced mate? It's actually a rather famous study sometime in the 1940s. I've seen it before.

Can somebody please tell me the answer? I'm not sure, I may have to send out Stockfish to help me...
Are you serious? Just keep clicking the little bulb under the puzzle and it will show you the correct moves.
You're an 1822 bullet. You bullet guys are supposed to be great at tactics. You should have nailed this endgame one.
Ever heard of the word 'joking'?
And seriously, do you know that the puzzle is a forced mate? It's actually a rather famous study sometime in the 1940s. I've seen it before.
I see that it's forced after you guys mentioned it, yes. I liked this one a lot and agree, it's a great position.
Sorry if I was a jerk...lots of sleeplessness, coffee, and study here.

There is only one move every time so the puzzle solves itself you know. d4 d5 ab b5 b6 b7 checkmate.

Can somebody please tell me the answer? I'm not sure, I may have to send out Stockfish to help me...
Are you serious? Just keep clicking the little bulb under the puzzle and it will show you the correct moves.
You're an 1822 bullet. You bullet guys are supposed to be great at tactics. You should have nailed this endgame one.
Ever heard of the word 'joking'?
And seriously, do you know that the puzzle is a forced mate? It's actually a rather famous study sometime in the 1940s. I've seen it before.
I see that it's forced after you guys mentioned it, yes. I liked this one a lot and agree, it's a great position.
Sorry if I was a jerk...lots of sleeplessness, coffee, and study here.
There is only one move here. 1. d4!! 2. d5!! 3. ab!! 4.b5!! 5.b6!! 6.b7 checkmate.
Why the hell is this difficult every single move is forced?