The Brain the main antagonist of Animaniacs, the overall titular deuteragonist of its spinoff Pinky and the Brain and Pinky, Elmyra and the Brain, and the main antagonist of the crossover series, The Plucky Duck Italian Adventures.
Vote which fictional character would naturally fit in-universe with a big-named franchise! No time-travel, no interdimensional crap, no "Pooh's Adventures", they would just exist in-universe.
