Black Manta is a fictional DC supervillain and is the arch-nemesis of Aquaman.
Black Manta decided that it would be best to form a temporary truce with the King of Atlantis known as Aquaman. He would help lead his forces to fight against Darkseid. But like Black Adam, once this fight is over, he resort to the second phase of his plan.
Black Manta appears as a boss and playable character in this crossover game between Lego Batman (hence the title) and Lego Marvel. He is hired by Hydra to invade Atlantis to steal DNA samples of the alien conqeuror Starro, Manta himself hiring King Shark for backup. While Shark is defeated by Aquaman and Green Lantern, Manta leaves with the samples, and destroys the facility the samples were being kept in. Manta is unlocked after the level (That Continent Southwest of Spain) is complete.