Koopa Troopas (Nokonoko (ノコノコ ^?) in Japan) are turtle-like creatures. They are the most common classification of Koopa. They come in multiple colors, including, green, red, blue and yellow. They first walked on four legs, but in later games they have both hands and feet. Their shells may be used as projectiles, which have become a fixture in all Mario Kart games. The Paper Mario series introduces friendly Koopa Troopas. Flying versions with wings, first introduced in Super Mario Bros., are called Koopa Paratroopas. Both Koopa Troopas and Koopa Paratroopas make cameo appearances in Super Smash Bros. Melee and Super Smash Bros. Brawl as enemies.