My favorite is Bog king from Strange Magic - Has a song talking about how evil he is. But all he does is prevent the spread of dangerous mind control magic, and quarantine people under the effects of said magic. Yes he greatly annoys people doing so, but honestly? If I get hit by a love potion, please quarantine me.
Okay, but you can’t say “he killed him” when he could be brought back by anyone. Especially since even the museum guy knew that the gun is for dehydration, so that means Megamind’s powers / gadgets are relatively known.