fight f8, g8, h8!

Its useful to know the endgame so you don't lose.  Here's a classic puzzle for the endgame.

Silman's Complete Endgame Course?

Let me see if I can take Black and stop you. 1...Ka7.  Your move.

 yes,  I'll play 2. Ka2

2.Ka3 is illegal...

I should have said, your turn to make a legal move.

I stirred up controversy

This is distant opposition.

And the number of squares between both kings is even so the side that moves has the opposition.

So, I think you messed up your moves somewhere, I remember reading this from an endgame book in spanish (just about distant oposition) and this exercise is from Silman´s endgame course (I believe), but I cant see how this exercise is valuable for practical chess.

Still waiting for your legal move.