A vertical slam that causes a destructive shock-wave.
The Stomp (ストンピング,Sutonpingu?, lit. "Stomping") is a move used by Sonic the Hedgehog that first appeared in Sonic Unleashed. It involves Sonic performing a powerful stomp into the ground to destroy enemies and obstacles.
When performing Stomp, Sonic first goes into midair, whether from jumping or entering midair. He then proceeds to slam directly downwards with one of his feet first, which creates a blue field around him. Once landing on the ground, Sonic releases a destructive shock-wave which damages the nearby surroundings. This is useful for destroying enemies and obstacles, breaking through weak surfaces and activating pressure pads. This move can also help Sonic reach the ground quickly.
The Stomp first appeared in Sonic Unleashed. In order for Sonic to perform the Stomp in the PS3/Xbox 360 version of the game, he has to possess the Level Up Item called the Stomping Shoes (In the Wii/PlayStation 2 version, Sonic starts out with all of the abilities including Stomp). Here, Sonic can perform the Stomp by pressing / while airborne.
The Stomp returned in Sonic Colors as one of Sonic's standard moves. He can perform the Stomp while airborne by pressing when just using the Wii Remote, the Z button when using the Wii Remote and Nunchuk and the X button when using the GameCube Remote and the Classic Controller. In the DS version, it is performed (while in midair) by holding down on the d-pad and pressing / and will create bigger shockwaves than in Sonic Unleashed when performed.
The Stomp reappeared again in Sonic Generations as one of Modern Sonic's standard moves with the same controls as in Sonic Unleashed. In the console/PC version of the game, the shockwaves it produces are virtually non-existent. However, if Sonic is equipped with the Power StompSkill, the range of the shockwaves from the Stomp are increased, thus allowing Sonic to damage more enemies in the vicinity. In the Nintendo 3DS version, Sonic has to obtain the Stomping Shoes before he can use the Stomp.
In Sonic Generations for the Nintendo 3DS, Tails created the Stomping Shoes. He also mentions that the reason Sonic can stomp with them is because they are lighter than his normal shoes.
In Sonic Colors, the Blue Wisp allows Sonic to do a different version of what appears to be the Stomp. When he lands on the ground, nearby enemies will be destroyed.
Sonic Colors uses a different animation for the Stomp (where a blue light engulfs Sonic) than in Sonic Unleashed.
In Super Smash Bros. Brawl, Sonic's D-Air move resembles the Stomp, but it is slower, goes diagonally, stalls before falling, has no field surrounding the landing, and sometimes does not fully activate if Sonic is too high.
Super Sonic's Stomp color is blue in Sonic Colors, but in Sonic Generations his Stomp color is gold.