User blog comment:Nausiated/Project 11/61 - Big Fish/@comment-11836-20140921174823/@comment-61022-20140922022108

There are some aspects to Immortus that don't fit to the "linear" timeline that is outlined in the Marvel Handbooks. In which case, I'll address them separately from the main narrative (just like the Handbooks do). As for his appearance in the X-Men animated series... It was a brief appearances in the Beyond Good and Evil. He wasn't integral to the plot at all. The only reason he's involved in the story at all (all be it briefly) is because Apocalypse uses Limbo as his battlefield against the X-Men.