594px-Professor Ratso
Professor Ratso is a villain from Champions Online, belonging to the Manimals- though, when first encountered, he appeared friendly and asked the hero to help him collect rare chemicals being stored in Moreau's lab: the player believes Professor Ratso is one of the rebel Manimals seeking to help humanity and thus honors the rat's request.

Yet, after retrieving the chemicals, it is clear Professor Ratso is actually a mad rodent who seeks to de-evolve humanity in Manimals on behalf of Moreau and had been using the hero as a pawn.

The player then fights Ratso and defeats him before he can do further harm.