An extremophile is a creature that thrives in an exceedingly hostile environment. The Ultimate Extremophile takes that Real Life
scenario Up to Eleven
. The natural habitat of an Ultimate Extremophile is the World of Chaos
. The place might even make sense from their perspective. They may have Reality Warper
powers, they may be frigtening, but they do not have to be evil. If they are, it borders on Eldrich Abomination
. Sometimes they can exist in other worlds, but they are only truly at home in a World of Chaos
, and that is their defining characteristic.