Origin
Triton is a deity of Greek mythology. He is a son of Poseidon and Amphitrite and serves as a herald to his father. His most notable role is in raising and training the Goddess Athena during her childhood. Triton is notably depicted as a merman in ancient artwork. His legend mentions numerous descendants with similar half-human and half-fish forms.
In DC:
Aquaman Year One
Triton first encountered Aquaman during the Sea King’s first year as a superhero. He tried to kidnap Wonder Woman from Paradise Island and force her to marrying him, easily overpowering the Amazon. Aquaman freed Wonder Woman and managed to turn the godling away from his quest. But Triton would not forget.
Claim as Champion of the Seas
He reappeared years later and under command of his father, the god of the seas Poseidon, he challenged Aquaman to a battle to the death for total command of the seas and all it’s life. Aquaman after a long and incredibly brutal battle defeated the godling for a second time, fatally injuring him on his own trident. Poseidon conceded defeat to Aquaman and gave him a part of his divine power, as a reward for the victor (that temporally overwhelmed and blinded Aquaman before he learned how to control it).
Triton’s Revenge
After Triton’s second defeat Poseidon grew annoyed with his son’s careless attitude who was content with his status as a godling and was now spending his days in a constant state of decadence. He berated his son trying to make him realize his divine potential, but Triton in turn managed to grab Poseidon’s Trident when his father was talking and stab him in the back, seemingly killing the powerful Olympian and absorbing his powers as the new god of the seas.
He then proceeded to exact his revenge against the man who had humiliated him in the past, Aquaman. He forced Nuliajuk (the mother of Monsters) to mutate an aquatic dragon like creature to enormous size (dwarfing the entire capital city of Atlantis, Poseidonis) and with his new pet he laid siege to Atlantis. The Atlantean guard alongside Tempest, Koryak and Dolphin where no match for Triton who easily defeated them. Aquaman and an army of sea creatures arrived to confront Triton, but the godling, now one with the entire ocean easily defeated Aquaman while his monstrous pet destroyed the artificial intelligence that kept Atlantis floating sending the city underwater again. Aquaman then goaded Triton into killing him, which the godling gladly did.
When the battle finished, Triton was in charge of the underwater Atlantis and Aquaman dead. Unknowingly to him though, Aquaman had gone to Tartarus (the greek underworld) because he was killed by an Olympian weapon. There he managed to save Poseidon from his brother Hades, and the two of them returned to face Triton. Poseidon took back his power and Aquaman defeated Triton yet again but was stopped from killing him from Poseidon. he said that a mortal has no right in ending a god’s life and proceeded to do so himself, seemingly killing his son. He then gave his Trident to Aquaman, acknowledged him as his champion and left to mourn his son’s actions.
Weakened but Alive
Triton reappeared as a villain in Wonder Woman’s book. Aquaman and Wonder Woman were investigating a heinous crime (the murder of a boat of full of children under Diana’s protection) and while they suspected Black Manta as the one responsible, they finally confronted the perpetrator, a weakened, deformed and stripped of most of his powers Triton (with help from his Gorgomaids). After being subdued by the godling, Wonder Woman managed to escape and break Triton’s neck, despite Aquaman’s protest. This made Poseidon appear who admitted not having killed Triton before. He berated Diana for killing his son, but gave her a pass since his crime was very serious.
One Last Appearance
During the events of World War III, Poseidon and seemingly Triton, alive again somehow gave Aquaman full access to his mystical Water-Hand, allowing him to raise the entire sunken city of Sub Diego, but losing his humanity in the process and transforming to the Dweller of the Depths.
Powers & Abilities
Triton (before he was stripped of his “godling” status by Poseidon) possessed vast god-like powers.
Superhuman Strength
Triton possessed vast superhuman strength. he was able to restrain Wonder Woman casually, using only one his hands and nearly defeated Aquaman in underwater battle (Aquaman prevailed due to his speed and skill).
Superhuman Speed (Underwater)
Triton’s speed underwater was far greater than most beings, with the exception of Aquaman.
Superhuman Endurance
Olympians do not tire and do not require sleep or sustenance (though they grow weaker with the lack of faith)
Enhanced Senses / Reflexes
Triton’s senses function normally even in the deepest part of the ocean, and he can move fast enough to engage Aquaman in underwater combat and dodge some of his attacks.
Underwater Adaptation
Triton is a water god and is at his most powerful in his domain, but can fucntion in every enviroment and on land.
Invulnerability
Greek Gods are virtually immune to harm, with the exception of divine weapons or special circumstances (being stripped from their powers). In the rare case they get injured, they can also heal and replenish their power.
Immortality
Triton, like all Olympians, is immortal and does not age.
Marine Communication
Triton was able to communicate with every creature living in his domain.
Size Manipulation / Shape Change
Like all Olympians, Triton can change his size and shape at will.
Energy Manipulation
Triton can channel his powers through blasts of energy with multiple effects.
Skilled Warrior
Triton has thousands of years of experience as a warrior on his father’s side, especially as a trident wielder.
Vast Knowledge
Triton has thousands of years worth of knowledge and is generally aware of everything that happens on Earth’s oceans and it’s inhabitants.
Weapons and Equipment
Triton’s Trident
Triton’s weapon of choice is a Trident. It can hurt even him, but it’s not indestructible (as Aquaman was able to break it on Triton’s back) nor does it posses as many powers as Poseidon’s Trident. It’s possible that Triton has an assortment of tridents or creates new ones when one breaks.