Voiced By: Hiromi Tsuru (JP)
- Affably Evil: Very polite and soft-spoken, until she fights.
- But Now I Must Go: Anime-only, when she changed back to her mermaid form and leaves.
- Cry Cute: "Milord Poseidon... now you're back to being Young Julian Solo..."
- Dark Chick: While she does have the fighting abilities, she's more of a messenger than a frontline fighter.
- Happily Ever After: In the end of the Poseidon Arc in the manga, Thetis changed back into a fish. Jullian/Poseidon comes back and finds her dead fish body and holds it gently in his hands. In the anime, it was happier where Thetis changes into a mermaid and you can see her leaping in and out of the water with the good guys staring at the sunset.
- Designated Girl Fight: Though she does give Shaina quite a run for her money.
- DistractedbytheSexy: Extreme aversion. Kiki openly insults her as an "ugly fish squid creature".
- Lady of War
- Meaningful Name: Thetis is a goddess of the sea and leader of the Nereids (sea nymphs) in Greek Mythology. As well as the mother of Achilles.
- Our Mermaids Are Different
- Perky Female Minion
- Mythical Name: After one of the Twelve Titans from Greek mythology. The mother of the rivers, springs, streams, fountains and clouds.
Sea Horse Baian
Voiced By: Show Hayami (JP)
- Barrier Warrior - Seiya notes that his fighting style is very similar to Misty's
- Blow You Away
- Smug Super
- Spell My Name with an "S": Baian or Bian?
- Villainous Breakdown: When Seiya quickly takes advantage of him and tells him that he's just a Smug Super without real merits.
Voiced By: Issei Futamata (JP), Gerardo Reyero (Latin America)
- Defiant to the End : Prefers to go down fighting towards Shun despite being bound in chains, trying to block Shun's direct attack (via Libra Cloth's weapons) on the pillar he protected. Shun is very impressed at his Undying Loyalty to Poseidon and expresses sadness at his passing.
- The Beastmaster: His power is to summon the abilities of six creatures.
- Mythological Name: From Io the sea nymph in Greek Mythology.
- You Gotta Have Pink Hair
- Real Men Wear Pink: Gave Shun a very hard fight and died awesomely.
- Senseless Sacrifice: Tries to keep Shun from destroying his pillar by shielding his body. Unfortunately, he never had a chance due to him being bounded up and the pillar itself being too big to protect all of it.
- Ambiguously Brown
- Blade on a Stick
- Dark-Skinned Blond: White-haired, to be more exact.
- Noble Demon
- Token Minority: The only dark-skinned Mariner of the group. Before you ask, he's from Sri Lanka.
- Well-Intentioned Extremist
Voiced By: Keaton Yamada (JP)
- Calling Your Attacks:
- Satanic Salamander
- Critical Research Failure: In-universe case. Had he bothered to scan Ikki's mind throughly, he could've found about Esmeralda earlier, therefor using her form to kill him. He could have won the war for Poseidon's side right there!
- Crowning Moment of Heartwarming: Invoked and weaponized! Yeah, he's a bastard.
- Dirty Coward
- Dying Dream: In his last moments, he imagined himself killing Ikki by taking Esmeralda's form.
- Gonk: We never get a proper look at his face, but he SEEMS to be one.
- Lean and Mean
- Last of His Kind: He's proud of it too. Ikki uses his Mind Rape against him by pretending that There Is Another.
- Master of Disguise
- No Yay: He managed to give Seiya an amorous hug so convincing, that he really believed he was his lost sister. Yikes!
- Required Secondary Powers:
- "The Reason You Suck" Speech & And This Is for...: He find himself in the receiving end of an incredibly satisfactory combination of this at the hands of Ikki.
- Shapeshifter Guilt Trip: His whole shtick.
- Voluntary Shapeshifting
Voiced By: Ryūsei Nakao (JP)
- An Ice Person
- Cain and Abel: With Hyoga, in the childhood friends sense.
- Died in Your Arms Tonight: Hyoga's.
- Eye Scream / Good Scars, Evil Scars: The result of saving Hyoga's life.
- Evil Counterpart: To Hyoga.
- Forgotten Fallen Friend: To be such an important person in Hyoga's life, it's quite notable that he didn't mentioned him before.
- Fallen Hero
- Knight Templar: He admires the Kraken because it would sink ships with sinful people on them. Hyoga questions this, as it would entail killing innocent people which just happened to be on board as well. Isaac still calls it the best way of making justice.
- Kick the Dog: Or better said, the puppy, as he kicks poor little Kiki when he brings Hyoga the Libra Cloth. That pisses Hyoga off enough to return to the fight.
- Kraken and Leviathan: However this particular Kraken has no Combat Tentacles and looks like a giant Ray fish.
- You Gotta Have Green Hair
- The Unfettered: What he always aspired to be, even before becoming a Poseidon's general.
- Would Hurt a Child: Poor Kiki, as already said.
Voiced by: Yoku Shioya (JP)
- Bishōnen: Very pretty, even by this show's standards.
- Good Wings, Evil Wings
- Musical Assassin
- Number Two: After the Poseidon Saga he remains by Julian's side, helping him aid the victims of Poseidon's flood.
- Not Quite Dead: Twice, if you count his supposed death in the Asgard Saga.
- Technicolor Eyes: Light red
- What the Hell, Hero?: To Kanon, after finding out his plans. To the point of trying to attack him.
- You Gotta Have Pale Purple Hair
- Undying Loyalty: To Julian/Poseidon
Sea Dragon Kanon
Voiced by: Kazuyuki Sogabe (JP, original series), Ryōtarō Okiayu (JP, OAVs and video games)
- BADASS: After his Heel-Face Turn and becoming the Gemini Saint, in the Hades Arc he singlehandedly kills more Specters than half the Gold Saints combined. Only Shaka and Dohko can compare in kill counts. He even has the honor of being the only Gold Saint to kill a Judge in the classic series.
- Cain and Abel: He's Saga's twin brother.
- Dragon with an Agenda: No pun intended. He tries to use Poseidon to rule the world.
- Heel-Face Turn: He becomes the Gemini Saint after Saga.
- Genius Bruiser: He is responsible for most of the conflicts within the classic series. He manipulated Poseidon into doing starting his next holy war against Athena earlier than scheduled, awakened the evil in Saga's heart and drove him into insanity, and ALMOST SUCCEEDED in gaining world domination until he made the fatal error of underestimating the main Bronzies.
- Evil Twin: To Saga.
- The Man Behind the Man.
- You Gotta Have Blue Hair