Kevin O'Neill was an English comic book illustrator who was the co-creator of Nemesis the Warlock, Marshal Law, and The League of Extraordinary Gentlemen.

Nemesis the Warlock is a comic series created by writer Pat Mills and artist Kevin O'Neill which appeared in the pages of the British weekly comics anthology 2000 AD. The title character, a fire-breathing demonic alien, fights against the fanatical Torquemada, Grand Master of the Terran Empire in Earth's distant future, and his attempts to exterminate all alien life.