Underlord Seedle is an Overlord-class being (despite the class and title of Underlord) and was once a famous human samurai, who lost his life when he attempted to rape Lady Salome, only to be stabbed and killed by her. Although Salome was burned at the stake for murdering a honored samurai, Seedle wasn't satisfied, and killed the ruler of the Underworld (called Hell or Hades in some cultures), becoming it's new ruler. Upon hearing that Zetta was in trouble, Seedle nonchalantly comes to help, aware that if Zetta's in trouble, Salome is bound to appear. When she does, him and her enter an argument, Seedle telling the Overlords of Salome's illness. (Leaving out the fact that she was diverting her Mana to Zetta) Near the end of Chapter Nine, Seedle appears before Zetta in an attempt to stop Zetta from dying along with Salome. Alexander interferes with Seedle, allowing Zetta to find and stop Salome. In the Good and Canon ending, he appears once again when Pram attempts to revive Salome by writing it as a wish in the Sacred Tome (Zetta at the time.) He knocks Pram out, stopping the ritual. However, Alexander appears again, attacking and fighting Seedle so that Pram may resume the ritual. It can be heavily assumed that Seedle was killed during his final confrontation with Alex, since he screams a death cry upon being attacked by Alexander's Vanishing Bolt.
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Despite being an honorable samurai, he isn't an honorable person. He carries an eternnal grudge against Salome, who he has attempted to kill on countless occasions. He also seems to be slightly sadistic, often gaining pleasure when Salome is sad or worries. He also doubts the alliance of the Overlords, yet tolerates since he is easily bored.
He is the only Overlord to lack a Mana Aura, usually drawing one of his katanas whenever in danger or battle-ready.
To recruit Seedle, a character must write the wish "I wish to fight Seedle!" upon reaching level 160 and having 7000 Mana. The stage is avaliable through Chapters 3-8 on a new cycle. The scene involves Zetta challenging Seedle for the hell of it, while Seedle attempts to tell Zetta the truth behind his power, only for Zetta to shrug it off, initiating combat. In battle he is a level 300 adversary, but if you were able to recruit Overlord Laharl and his cohorts, then you should be able to recruit Seedle within the same power used to defeat Laharl.
In battle, Seedle is an ATK-based character who also dabbles in TEC. He is good with Katanas, Spears, Fishing Poles, and Makai Cannons. Seedle's main weapon is the Katana, however, a Spear is much more useful (Though weaker) if leveling him up quickly is the intention of the player. He has 140% Aptitudes in ATK and HP, but also has 110% in TEC. Therefore, if you wish for Seedle to use TEC-based weaponry, you must reincarnate him once or twice as well as give him Glasses accessories in order for him to wield them properly. His unique skill "Dark Revenge" is a single-target ATK-based skill dealing moderate damage.