Whomps are large enemies appearing in Whomp's Fortress and Bowser in the Sky. They move along a predefined path until detecting Mario in a frontal radius. Upon detection, they will fall towards Mario and attempt to crush him. They can be defeated by ground-pounding on their back whilst laying horizontally.
Whomp patrols a path with a length of 700 units in Whomp's Fortress and 200 units in Bowser in the Sky. Whomp walks forward with a forward speed of 3 units/frame until the distance from its home exceeds the length of its patrol path. When this occurs, Whomp stops, turns at 5.625 degrees/frame for 32 frames, and begins patrolling again. If Mario is within 45 degrees of Whomp's line of sight and within 1500 units of its location, Whomp accelerates to 9 units/frame to chase Mario. If Mario is then within 300 units of Whomp, Whomp stops and begins to jump with a y-velocity of Whomp's y-velocity is set to 40 units/frame. Then, Whomp's facing angle rotates at 1.40625 degrees/frame until its facing angle is 90 degrees. Once Whomp has hit the ground, it will stay in its grounded state for 100 frames if it did not squash Mario and 30 frames if it did squash Mario. If Whomp gets up, it rotates upward at 2.8125 degrees/frame until it is upright again and returns to patrolling its path. While Whomp is down, if Mario stands on Whomp and then moves off, a coin is spawned. If Mario ground pounds on Whomp, 5 coins spawn, particles spawn, the screen shakes, a sound is played, and Whomp is deleted.