Mate in 5 Exercise 76

Black plays and wins in 3 moves https://lichess.org/weEvaR79/black

1... Nc5 2. Ka8 Nxa6 3. bxa6 Rxa6#

The analysis board does checkmate in 5 moves

1... Nc5 2. b6+ Kxc6 3. Ka8 Rxa6+ 4. Kb8 Kxb6 5. Kc8 Ra8#

Source:

This publication is in my collection "500 chess puzzles. Mate in 5. Advanced & Expert Level."