By A Mystery Man Writer
Black Manta, Villains Wiki
Ocean Master (Young Justice), Heroes and Villains Wiki
Who is the most crucial comic book character in the DCEU (DC Extended Universe)? - Quora
Nereus (DC Extended Universe), Movie Heroes and Villains Wiki
Vigilante (DC Extended Universe), Villains Wiki
DCEU: Every Main Villain, Ranked By Power
Savant (DC Extended Universe), Villains Wiki
Wonder Woman (DC Extended Universe), Heroes and Villains Wiki
not counting Black Manta and Ocean Master, these are all the old villains that have showed up in recent years, at least since the new 52. : r/Aquaman
DCEU Villains DC Extended Universe(DCEU) Amino
Thaddeus Sivana (DC Extended Universe), Villains Wiki
Reverse-Flash (DC Extended Universe), Villains Wiki