Red Koopa Troopa
The Red Koopa Troopa is a variation on the standard Koopa Troopa. The Red Koopa Troopa appears in SSBM and SSBB. None exist on their own, but lightly attacking or jumping on a Red Koopa Paratroopa will create one. They may also spawn from a Red Koopa Shell, although the only way to create one is to kill a Red Koopa Troopa, which defeats the purpose. In Super Mario Bros. red Koopa Troopas would turn to the opposite direction when they reach an edge, while the green ones simply fell off.
In Melee
Only two Red Koopa Troopas (actually one Red Koopa Paratroopa) are found in the first stage of Adventure Mode. Unlike its green counterpart, the red shell will have a fire damage effect when thrown at enemies, though it will not set its sights on random targets.
In Brawl
Red Koopa Troopas are an enemy wherever Bowser's minions are found in the Subspace Emissary, which are usually the forest levels involving Diddy Kong as well as the Great Maze
Trophy Description
A turtle in the employ of Bowser. Koopas formerly traveled on four legs, but they've recently been spotted strolling on two. This has freed up their hands, allowing them to chase Mario with nets. Their adaptability must make Bowser very happy indeed. Unlike their green- shelled brethren, red ones do about-faces when they run out of road. They're a bright group.
Trivia
- Oddly enough the actual Red Koopa Troopa does not appear in SSB unlike its green counterpart on the Mushroom Kingdom stage, but the Red Koopa Troopa shell does make an appearance as an item.