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1. Rxh5 h6
2. Rxh6 g5
3. Rxh8+ Kxh8
4. Ke3 and the king will catch the knight.

Yeah but how long will it take.

  1. Rxh5 h6
  2. Rxh6 g5
  3. Rxh8+ Kxh8
  4. Ke3 Kg7

Not long.

I assume then you are playing Kf2 then.

You're right, too many variables, my brain is cooked. The only long shot I see is to let the White King take the Black Knight while the Black King goes to the other side of the board to help out in a pawn massacre.