A Koopa is a turtle like, intelligent creature that lives in the Mario Universe. Their shell color ranges from the lightest of greens to the darkest of reds. In the Mario Universe, Koopas are harmless and are citizens. However, Koopas who serve the Koopa Empire also called the Koopa Troop are highly hostile. Koopas branch off into many subspecies including Paratroopas, Magikoopas, Spikey Koopas, Dry Bones and more. Koopas have been known to carry and use firearms along with that they are masters at close-combat.