2. Ke6 Qc8+ 3. Kf7 Qc7+ 4. Kg6 Qxh7+ 5. Kxh7 and then 6. Bf1# can't be stopped. Am I missing anything?
10 moves to checkmate!

Loomis, yes, the sequence is lengthened somewhat by Qd8 instead of Qxh7+. It's still a faster mate, though.

Ah, good catch, I didn't think of interposing the queen at h4.
So, 4. ... Qd8 5. Bxf1+ Qh4 6. Nxh4 and now there is a new threat of Qf3+ followed by Qg2#. If 6. ... Kg1 7. Qf3 Kxf1 8. Qxf2#.
So this is a mate in 8? Or is there still something missing?

But now your puzzle doesn't have a unique solution.
After 6. Nb6+ black can play either 6. ... axb6 as you show or 6. ... Bxb6.

Players, which move was "the toughest"?
Please, rate it (the puzzle) from 1 (bad) to 10 (great). I need some feedbacks!

chessbeginner, after 2. ... Ke6 white has 3. Qc8+ to prolong the game.
brown, you're missing Qxd6+ followed by f4 to make an escape for the king and delay checkmate.
The alternate king moves are a bummer. :-)

IT WAS SO EASY YOU NOOB
Here is it. I hope you like it.
Good luck!
P.S.: Look at post #12
Here is it. I hope you like it.Good luck!
P.S.: Look at post #12