Mr. Wrinkles is Two-Legs Joe's toy back in the past. He mostly says sentences about loving Joe even though they are not true. Entrèe threw him in the volcano in the episode "Mr. Wrinkles in Time" because Mr. Wrinkles was going to be the new mayor of the town and torture Joe instead of loving him.
When Peri and Entrèe went back in time to save Mr. Wrinkles, when the young Joe still played with him it was revealed that Mr. Wrinkles was actually evil all along.
Peri and Entrèe had no choice to fix the future, so they went back to the past again, they have to throw Mr. Wrinkles into the volcano again. After he was thrown in, the young Joe stomped him and then the future Entrèe punched him into the volcano. It was unknown if the young Joe survived after the future Entrèe punched him.