The Mayo Monster is a monster made from mayonnaise that Entree made. He was supposed to be the most delious mayonnaise ever, but it turned out to be a monster putting everyone in a jar and Entree in what seems to be a small ketchup (or mayo) bag. At the end of Mo' Mayo, Mo' Problems, a female ketchup bottle called him Albert. He is voiced by Lawrence Bayne
- He can't fight his instincts with a B.L.T. sandwich.
- He hates it when people (such as Entree) land on their funny bone and get injured.
- He must be avenging all the condiments that have been squirted out of their "homes" by putting everyone in a jar.