Thwomp (ドッスン, Dossun) is an enemy from the Mario series.
Thwomps are recurring Mario enemies, debuting in Super Mario Bros. 3. They hang in the air, and when players passes under them they try to crush them by falling. They are often found in castle levels and have a variety of subspecies such as Thwimps, Tox Boxes and Whomps.
One of Kirby's possible Stone transformations is based on a Thwomp, using the blue design from Super Mario 64. A Thwomp also appears as a trophy using its main design which originates from Super Mario Bros. 3.
As in Melee, one of Kirby's possible Stone transformations is the Super Mario 64 Thwomp design.
Thwomp appears yet again as one of Kirby's possible Stone transformations; however, its design is now based on more modern Mario games.
The Thwomp trophy is exclusive to Super Smash Bros. for Nintendo 3DS.
As an Assist Trophy
Thwomp makes its debut as an Assist Trophy. It behaves exactly as it does in Mario platformer games: it hangs in the air, and falls down when characters pass under it. However, unlike the games it appears from, Thwomp will teleport to a different part of the stage if unactivated for a while. Training Mode describes the Assist Trophy: Squishes opponents caught beneath it. Can't be KO'd.
Notably, the Thwomp itself is solid and cannot be passed through, but cannot be stood on, as players will just be forced to the side should anyone attempt to fall onto one. Touching one at rest does no damage as the Thwomp's hitbox only manifests at its underside while it is falling.
As in SSB4, the modern Thwomp design appears as one of Kirby's possible Stone transformations.