Tokyo, Japan. During the party, Mater comes to his stand and asks what he has that's free, but he doesn't respond. Mater then sees the wasabi and thinks that it's pistachio ice cream. He asks for some, and he gave him a little bit. Mater kept asking for more and more until Daisu finally gives him a big scoop. Mater tries the wasabi, and burns his tongue badly, so he ran somewhere quick to find some water, and he drank from the water from a fountain. Mater says into the microphone not to eat the free pistachio ice cream, because it had turned.
That scene was also in Mater's nightmare.
In the video game, he's a playable character.