I'll Start:
Abraham Van Helsing (Hotel Transylvania 3: Summer Vacation)
Amon Goth
Absolute Solver
AM
Anton Chigurh
Alex DeLarge
Ahmanet
Aku
Albert Wesker
Aaravos from The Dragon Prince
Azula (Avatar: The Last Airbender)
Alpha (Up)
Arry (Thomas & Friends)
AUTO (Wall-E)
Andrew (Tangled)
Amon (The Legend of Korra)
Anti-Wanda
Aiwei (The Legend of Korra)
Alaskan Bull Worm (SpongeBob SquarePants)
Adolf Hitler
Abaddon the Despoiler
Alma
What do you think?