What did Satan ever do that would give him such a bad reputation? Why should anyone be afraid of him (or them)? What exactly did Satan do that makes him deserving of the lake of fire, and the title of Pure Evil?
Canonical references requested.
Purported actions by Babylonian gods do not apply. Even if they did, I need to see some moral reasoning behind his (the ancient god in question's) damnation, and evil reputation.