Mega Koopa

The Mega Koopa is a giant Koopa Troopa in Super Paper Mario that got a Mega Star.

Once an ordinary Koopa Troopa, it sees Mario coming and runs for its life. It hits a block containing the Mega Star and turns huge (using the same animations that any other character does when he or she uses a Mega Star). Mario or Princess Peach (Bowser and Luigi can also encounter it once they join the party later on) needs to become giant by using a Mega Star to defeat the Koopa, but it can also be defeated by an explosion of Boomer, Bowser's fire breath, Luigi's Super Jump, picking it up and throwing with Thoreau, or by succumbing to the effects of a Catch Card SP. Oddly enough, when looked at in 3D, the Mega Koopa is 3D instead of flat, though all "Mega" characters may have this characteristic. This Koopa is not to be confused with a Gargantua Koopa Troopa.

Trivia
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 * This is perhaps the only occurrence of a regular enemy using a power-up item in a Mario game, though they were originally going to in another platformer, New Super Mario Bros..
 * When the player receives 100 shop points, he or she is given a Catch Card of the Mega Koopa.
 * According to the InterNed, the music playing when Mario, Luigi, Peach of Bowser uses the Mega Star is called "An Unrivaled Battle".