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From Unmariowiki

Ronald McDonald is a clown who is in the fast food buisness. He has appeared as a boss in all of the Mario RPG games. He is encoutered by going to mcdonalds, and finding out their recipe- 1-up mushrooms. Ronald will get mad and say IM LOVING IT in every game. In the battle field, he attacks by throwing hamburgers at the player. He also appears as an unlockable player in all of the Mario Mart games, and has the greatest speed with the red Shopping Cart.