The whistle plays a rhythm — tap it back in the next bar, exactly the same. Get it right and the wall, window or chimney comes down. Spacebar or a screen tap, one button is all you need.
The whistle plays a rhythm, and in the next bar the robot Beat taps it back, smashing walls, windows and chimneys. Listen with your ears, hit with your hands.
Smash the wall, break the window, topple the chimney, rip off the planks, and a remix of all of them. Hard mode is faster and gives you a single heart.
There is also a hidden stage: no judging, no lives, just smashing — "Stress Smash!", at the top of the world map. Keep the combo going and it speeds up, with missions and a giant wall.
If your timing keeps drifting, try Calibrate timing on the world map once. It compensates for the audio delay that differs by device.