Air Date: October 10, 2009
Once you complete the game once you can go back to the completed levels to gain more sound bytes, capture different carros, and get to fight through the enemies and bosses which have a significant level boost. In some cases new bosses will appear along the way too.
The highest leveled up boss occurs with zenothlee where he enters the fight at a whooping level 200. I show my battle with the leveled up zenothlee and the following character stats: