Chess Online

Hmmm.
I don't like the puzzle after black plays 5.gxf5... I see now that it's an advantage, but it's really hard to accept a rook trade as white's goal here. ^^

If 5... gxf5 then it will continue:

6. Re2+ Kd7 (if Qe5, then 7. Rxe5+ leads to an obviously won position)
7. Qe8+ Kc7
8. Re7+ Kb6
9. Qb8+

9... Kc6 results in the immediate trade of a queen for a rook, as follows:

10. Qb7+ Kc5
11. Rc7+ Qxc7 (the king has no moves)
12. Qxc7

If 9... Kc5, then it will take longer, but the result is just the same:

10. Rc7 Kd5 (or trading the queen for the rook straightaway with Qxc7)
11. Qb7+ Ke5/e6
12. Re7+ Kf6
13. Rxf7+

Now, Kg5 or Kg6 walk into a mate in 3, so the king has to come back.

13... Ke5/e6
14. Qe7+ Kd5
15. Rxf5+

The rook is now on the same rank as the black queen and will pick it up once the king moves.