Black Manta (Aquaman)

Black Manta is a villain character by DC Comics. He is Aquaman's arch nemesis.

History
In the 2003 version of his origin story, Black Manta (David Hyde) was institutionalised in Arkham in his youth. Autism was poorly understood back then, and he suffered treatments such as mechanical restraint and being smothered with a pillow to stifle his screams. The feeling of cotton sheets was very painful, but he found great sensory pleasure in ice cold water. He was shown to be repeating words and phrases such as "love swim" while watching Aquaman on the television.

David was exposed to various experimental treatments, one of which produced results which he himself describes as "my head feels clear for once". Unfortunately, this treatment also caused him to be extremely violent, and he kills one of the doctors.

Much later, as an adult and having already established Aquaman as his nemesis, he is knocked out during a fight against Aquaman and various other heroes. Aquaman uses his powers to look inside Black Manta's thoughts and seemingly cure Black Manta of autism. Black manta himself once again describes this with "my head feels clear for once."