Stomp

A stomp is the second part of a jump that occurs while coming down. The player does not have to jump; a stomp can be performed any time Mario is falling, whether from a ledge, cliff, or Pipe Cannon. If the character stomps on top of an enemy or switch, he/she can defeat the enemy or activate the switch. Stomping on enemies is Mario's primary attack, but it won't work on spiked, ghostly, underwater, or fiery enemies (if attempted, Mario can take damage). Boos also cannot typically be stomped on in the platformer games, but they can in some other games, such as certain Mario Party minigames. Stomping is also present in Super Smash Bros. Brawl and Super Smash Bros. for Nintendo 3DS / Wii U, where it deals no damage and is known as Footstool Jumping. Anyone who can jump has the ability to stomp. In the Mario role-playing games, Mario uses it with a Action Command for extra damage. In the Mario Party series, the player can jump on a rival to stun them briefly, though it is still not as strong as a Ground Pound.

Stomp Badges
In the Paper Mario series, various badges can add effects to Mario's stomp ability.

Sleep Stomp

 * BP: 1
 * FP: 2
 * Lets Mario do a Sleep Stomp. Uses 2 FP. If it works the enemy Mario jumps on falls asleep for a bit. It makes the enemy sleep which skip's the foes' turn until attacked.
 * It is only available for sale at Rowf's Badge Shop for 75 Coins.

Dizzy Stomp

 * BP: 1
 * FP: 2
 * Lets Mario do a Dizzy Stomp. Uses 2 FP. If it works, the enemy Mario stomps on becomes dizzy. It also paralyzes the enemy for a short time. When dizzy an attack might miss 50% of the time.
 * This badge can be found within a chest in the lower southwest area of Mt. Lavalava. Mario will need the Ultra Hammer to break the Steel Block guarding the room containing the chest.

Power Bounce

 * BP: 2
 * FP: 3
 * Lets Mario do a Power Bounce. Uses 3 FP. Jumps on one enemy continuously until Mario misses an action command. The damage will decrease by 1 for each Jump following the second.
 * Near the entrance to the Koopa Bros. Fortress is a room filled with several jail cells. Two of them can be entered by using Bombette to blow up visible cracks. One cell contains a key; the other one holds this badge.

Sleepy Stomp

 * BP: 1
 * FP: 2
 * If executed correctly, has a chance of making the enemy go to sleep. Its success rate depends on the enemy and makes the enemy sleep which skips the foes turn until attacked.
 * It is also found on the 10th floor of the Pit of 100 Trials. This badge is also easily bought at The Lovely Howz of Badges.

Soft Stomp

 * BP: 1
 * FP: 2
 * If executed correctly, makes the enemy "soft", which decreases their defense. Its success rate depends on the enemy and drops defense by three. It is similar to the D-Down Jump.
 * The badge can be found in the residential area of the Rogueport Sewers (Near Merluvlee's house, in the bottom left corner of the map) in a treasure chest.

Shrink Stomp

 * BP: 1
 * FP: 2
 * If executed correctly, makes the enemy smaller, decreasing their attack power. Its success rate depends on the enemy and drops attack by three.
 * It's located in The Great Tree, in the area with all the water that Mario has to drain out. To get it, Mario must Jump on the center log to reach it.