Complex sentence: Dougie has only appeared in cameos since Simpsons Already Did It, him and Professor Chaos join Christopher Reeve's Legion of Doom in Krazy Kripples during a short cameo.
Split into simpler sentences: Dougie has only appeared in cameos since Simpsons Already Did It. He and Professor Chaos join Christopher Reeve's Legion of Doom in Krazy Kripples during a short cameo.