|Real name:||Kimon Tanaka|
|First Appearance:||Aquaman #26 (December, 1994)|
|Created by:|| Peter David|
Kimon Tanaka was a sea captain who hunted dolphins for a living. He captured several dolphins for the Shinobi research centre, one of whom was Porm (Aquaman’s Dolphin Mother). When Kimon’s boat was destroyed he was left by Aquaman to be eaten by sharks. However, Kimon was rescued by his brother Tanaka, head of Raiden Industries. Tanaka rebuilt his brother’s body, turning him into a cyborg.
After finding his adoptive mother dead, Aquaman and Dolphin, ask Martian Manhunter to help them bring Demon Gate to justice, but it would involve invading Japan. Tanaka, afraid that Aquaman would declare war on Japan, turns off his brother's armor and gives it to Aquaman. He intended to kill him, but in communication with the fish that met his adoptive mother, he decided a new destination for Demon Gate, leaves him in the deserted island, where they would be fed on by algae until his death.
- Black Manta's Helmet: Gave him the ability to breathe under water and could project energy blasts.
Body Armour: Besides providing protection from physical and energy attacks, armor gives him:
- Enhanced Strength
- Enhanced Endurance
- Enhanced Vision
- Tracking: Demon Gate can track homing beacons placed on people.
- Wrist Flame Thrower