Thorg

Thorg was a pre-Marvel comics character featuring in Tales to Astonish, 1961 - this makes him one of Marvel's earlier supervillains, since the "official" Marvel age is not usually seen to begin until after the release of the first Fantastic Four comic (which sparked the "modern age" of Marvel canon).

Like all characters and events in the "pre-Marvel" comics Thorg is not canon in the current Marvel universe but is also not completely eliminated from said canon - rather he can be considered "in limbo" until writers or events within the "mainstream" Marvel universe counter his existence one way or the other.

History
Thorg was one of many agents for an alien race who scattered such agents across the universe in preparation for invasion, Thorg and several like him would end up buried up to their neck on a South Pacific Island, where they remained in hibernation for centuries.

Eventually an archeologist named Linus accidentally awoke Thorg and the alien declared his intentions of awakening his fellow agents, yet Linus convinced Thorg that the island was the entirety of the human race and the prideful alien decided he didn't require the aid of other agents to conquer such a small world.

Thorg subdued the local population then signalled his masters from space, who arrived the next day, yet in that time Linus made his way to a nearby volcano and induced an eruption via tossing dynamite into said volcano : the eruption would destroy Thorg and his superiors, who were too heavy and slow to swim to safety.

Trivia

 * while not named it is obvious that the island in question was meant to be Easter Island, famous for its statues (which Thorg's design is inspired by).
 * Thorg is only one of several stone-like aliens who used Easter Island Heads as a disguise, others included the Lithodia Rexians and the Stone Men.