Koopa Troopa

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One of the members of the infamous Koopa Troop, its shell can be kicked after this foe has been stomped.

Green Koopa Troopa is one of the enemies that you'll encounter early in the game. Mario will automatically vault over Koopa Troopa when running, but will cause Mario to lose a life if you hit one from below.

Shell

If you jump onto a Koopa Troopa, or jump while vaulting them, they'll retreat into their shell which will propel forwards, knocking into and killing enemies further along the stage.

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