Fantastically instructive Nimzo Indian/Dutch game!

The following game is taken from the notes of 222 opening traps after 1.d4, by Karsten Muller and Rainer Knaak, which I highly recommend. I am posting this following miniature on the blog not only as an example of the kind of gold you can find in this book, but also because it contains so many great mating patterns and queen sacrifices. The following is a small note in a larger game containing great analysis and traps at every turn, for the sake of clarity i have chosen a single position to consider.
The above position was reached after 1.d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 0-0 5. Bd3 b6 6. a3 Bb7 7.Nf3 Bxc3 8.bxc3 Ne4 9.Qc2 f5 10. 0-0 Rf6 11.Nd2 Rh6 12.g3? Qh4!

13. Nf3 (Obviously if 13. gxh4, then Rg6+ 14. Kh1 Nxf7#) 13…Ng5!

Now, mate is unavoidable.