Aunt Minerva

Through his adventures, Fawcett Comics/DC Comics superhero Captain Marvel and his Marvel Family gained a host of enemies, including the following:

A Jekyll and Hyde-type who fought Captain Marvel Jr.

Based on the Nazi Dictator Adolf Hitler. Führer of Nazi Germany, he was a member of the Monster Society of Evil. He ordered the creation of Captain Nazi, and caused many plots against America and its superheroes. Like his real-life counterpart, he probably committed suicide with his wife when the Allies were advancing to Berlin.

Only appearing in Marvel Family #27. Created by a scientist who thinks if everyone in the world was like him there would be no war. By studying amoebas he creates a serum that makes him split into two, and tells his duplicate to begin committing crimes. Captain Marvel captures him but he splits into two, Mary captures this duplicate, but the same thing happens, and the same with Jr. The captured duplicates multiply into 12 and break out of prison. Over the next few days hundreds of Amoeba family members are produced. The Marvels make an anti-fission formula and put an ad in the newspaper from Amoeba #56 to meet in the Grand Valley at noon, armed, to decide who should be leader. They argue and battle each other until finally only the original is left. The Marvels throw him into an anti-fission formula they created, stopping his splitting power, and then jail him.

One of a trio of monsters summoned from the Netherworld in Marvel Family #21 which also includes a Satyr and Hydra. Argus has multiple eyes allowing it to see and dodge Captain Marvel Jr's blows, but he defeats it by using a pot of paint to blind him, and the monsters are then sent back to the Netherworld.

George Tweedle was a fire insurance salesman who ingested a potion which transformed him into a demon-like larger being known as the Arson Fiend. The Fiend had the power to set anything he touched on fire and set fire to buildings that did not buy fire insurance. He also appears to possess superhuman strength and durability. He sends a note to Billy saying he will give him information about the Arson Fiend; when Billy gets to the area he invites him in, then knocks him out from behind with a club, ties him to a chair and gags him, then reveals himself, claiming to have discovered Billy's identity through unexplained means. He leaves him to die in a burning building, but Billy escapes when his gag slips off—enabling him to transform. After a battle on top of an oil tank, an explosion is caused and the burnt body of George Tweedle is later found by Billy. Originally a one-shot villain created for Captain Marvel Adventures #2 in 1941, the Arson Fiend was reintroduced in the 1990s Power of Shazam! series, where he gained the ability to shoot fireballs as well. Here he survives the explosion, but goes into a coma, and is given his powers back by Blaze, trying to take revenge on Ebenezar Batson, who wanted to turn off his life support machine.

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