[ His nerd offences have died down. Now it's time to explain. ]

Captain America and the Hulk got theirs from genetic alterations. Pushing the human limits to an extreme. Tony Stark has a robotic exo-suit that does essentially anything he wants.

[ Q starts counting with his fingers. ]

Hawkeye and Black Widow are just exceptionally good at fighting. Ah! The Scarlet Witch is magic as well.