Mate in 4 - the art of redeployment

Originally posted by SwissGambit
c5 is not legal.

Why? And what about Rxf4?

Originally posted by DeepRed
Why? And what about Rxf4?

The Black pawns are playing down the board.

if c3: Bg7, D4, Bf8! 🙂

Originally posted by doodinthemood
if c3: Bg7, D4, Bf8! 🙂

Originally posted by DeepRed
And what about Rxf4?

Solution:

1.Rg6! threat 2.Ne6+ Kd5 3.Ng7+ Kd4 4.Nf5#

1...c3 2.Bg7+ Kc5 3.d4+ Kb4 4.Bf8#
1...Rxf4 2.Rd6+! Kc5+ 3.Rf6+ Kd4 4.Rxf4#

Each threat and variation features the redeployment of a specific White piece.

I did not see that last variation. Nice.