Heroes • Ren (voiced by
George Newbern) – The prince of the once-grand kingdom of Octopon and the main protagonist of the series. Ren was raised by a
lighthouse keeper on the outskirts of his homeland, unaware of his destiny and heritage. He wields the broken sword that belonged to his father in its whole form. • Niddler (voiced by
Roddy McDowall in the miniseries,
Frank Welker in the TV series) – A monkey-bird who once belonged to Bloth until he escaped by aiding Ren's escape from the pirate captain. He hails from the island of Pandawa. Niddler is usually depicted as a little greedy and constantly ravenous for food, his favorite food being minga
melons, but he likes Ren and his ability to fly often comes in handy. • Tula (voiced by
Jodi Benson) – Tula is an ecomancer with the ability to control the elements and biological life, both sentient and non-sentient, as well as a natural affinity towards nature and animals. She is headstrong and often flusters Ioz. Tula is introduced as being a simple barmaid, but she stows aboard Ren and Ioz's ship, claiming she "wanted to get away from the drudgery of life on land". • Ioz (voiced by
Héctor Elizondo) – A rogue and pirate who joins up with Ren initially for the promise of treasure. Throughout the seasons, his character matures and he becomes fond of Ren and his idealism, evolving into a protective brotherly figure to him and often risking his life for Ren and the quest for the Treasures.
Recurring characters • Zoolie (voiced by
Dick Gautier) – A jolly, redheaded rogue who runs a gamehouse in Janda-Town. • Teron (voiced by
Dan O'Herlihy) – An ecomancer who sprouts roots from his body to replenish himself while away from his homeland, Andorus. Bloth uses his power for evil, in turn exhausting the local environment and its positive life energy. Tula has great respect for him as an ecomancer and brings him back to Andorus to heal the island of the Dark Water. Teron also helps Tula adjust to her new powers as an ecomancer when they first manifest.
Villains • Bloth (voiced by
Brock Peters) – The pirate captain of the feared pirate ship
Maelstrom and one of the primary antagonists of the series. Bloth is after the Thirteen Treasures of Rule to gain control of the Dark Water. He destroyed Primus's fleet seventeen years prior to the timeline of the show and captured Primus and his aide Avagon, though the seven captains accompanying Primus were able to escape with the Treasures. Bloth has since been hunting them obsessively and destroying every remnant of the House of Primus just as obsessively. • Constrictus - A worm-like creature who lives in the bowels of the
Maelstrom. Anyone who displeases Bloth gets thrown to the Constrictus. • Mantus (voiced by
Peter Cullen) – Bloth's second-in-command with long limbs, hands, and feet and
insectoid-like traits. He offers his cool and calculating personality as a battle strategist for Bloth's fleet. • Konk (voiced by
Tim Curry) – A pirate who works for Bloth. He lost his right leg thanks to a close encounter with the Constrictus. For a long time, Konk was the only one to ever survive being thrown to the monster. Although not particularly smart, Konk possesses more bluster than most of Bloth's crew and is always trying to win Bloth's praise. • The Lugg Brothers (voiced by
Earl Boen and
Frank Welker) – Two huge, dimwitted super-strong siblings who are members of Bloth's crew. • The Dark Dweller (voiced by
Frank Welker) – One of the primary antagonists of the series. The Dark Dweller is a powerful, evil creature that created the Dark Water. He had the Treasures originally scattered because their power is the only thing capable of opposing him and his evil master plan to swallow Mer in Dark Water. • Morpho (voiced by
Neil Ross) – A servant of the Dark Dweller and the leader of his worshippers, the Dark Disciples. He joins forces with Bloth and serves as the above-water liaison for the Dark Dweller, so that they can aid each other in their mutual goal of killing Ren and his friends, though they have two very different goals for the Compass and Treasures. Morpho was once an
alchemist until he was captured by the Dark Dweller and transformed into a
chimeric form resembling a variety of sea creatures. • Joat (voiced by
Andre Stojka) – A pirate and the previous owner of the
Wraith, which was stolen by Ioz. He uses his metal claw in place of his left hand mercilessly in battle. ==Ships==