Yes, there are only Kings in this puzzle. No, it's not an error. And yes, there is a purpose!!

Since you've made this far reading it, here it goes... White's goal in this possition is to dominate eighter one of the f8 or h8 squares. Use you're knowledge of opposition and outflanking to conquer this objective. Good luck, and leave you're comments after!

 TIP: To conquer this objective, White must first go to the kingside of the board.

This is an excellent test of your knowledge of the opposition and outflanking. It's easy if you understand them and there's good commentary in case you don't.