Glass Cannons

Glass cannons are obstacles encountered in Checkpoint 7 and Endless Mode. They fire cubes out of circular holes with cannons inside them. The cannons emit light when preparing to fire. Mayhem Boss can also be considered one, because it also fires cubes out of its "cannon".

How it works
The glass cannon works by detecting how far you are from the obstacle. Once close enough, the cube will be fired and you need to throw Balls to smash it. Occasionally throwing a ball at the cannon before it fires will make the cube fall down.