3-D Man

A-Bomb (HAS)

A.I.M.

Aaron Stack

Abomination (Emil Blonsky)

Abomination (Ultimate)

Absorbing Man

Abyss

Abyss (Age of Apocalypse)

Adam Destine

Adam Warlock

Aegis (Trey Rollins)

Aero (Aero)

Agatha Harkness

Agent Brand

Agent X (Nijo)

Agent Zero

Agents of Atlas

Aginar

Air-Walker (Gabriel Lan)

Ajak

Ajaxis

Akemi

Alain

Albert Cleary

Albion

Alex Power

Alex Wilder

Alexa Mendez

Alexander Pierce