In Hydranoid's unevolved form he walks on four legs, has three purple teeth jutting out from his upper jaw, and a long neck and tail. It also has pink spines running from the middle of its neck to about the end of its tail, which somewhat resembles the tail of a stegosaurus. In addition to this, he has a large pink horn on its nose and red eyes. It also has the starting of the blade in the center of its chest although it cannot move yet. As he evolves, he gains one more head.
Its entire body is composed of a highly intelligent, independent cell structure. His tail can be a very dangerous weapon along with his bite and power blasts.
Bakugan Official Handbook
Hydranoid is a hulking dragonlike beast with sharp spikes all over its body. It is even more ferocious than it looks. This vicious Bakugan is known for being cruel and merciless in battle. It takes pleasure in pounding opponents with its tail.
Bakugan Ultimate Handbook
Hydranoid's unevolved form is tough, too. The special cell structure of this Bakugan makes it difficult to injure in battle, and it's fighting abilities makes for a formidable attack. Hydranoid's long, spiked tail has sent more than one foe to the Doom Dimension!
Masquerade has complete power over Hydranoid; its ultimate evil master. As his partner, it is cruel and merciless in battle and feeds off of the energy gained from defeating an opponent. Masquerade uses Hydranoid to become the ultimate Bakugan so that Hydranoid can hold and bring the Infinity Core to Naga. It is later revealed that Masquerade wants to become the greatest Bakugan Brawler in a battle with Alice and Exedra in the Doom Dimension. Based on the words he uses, his motive for fighting for Naga is for the glory of being great in battle.
As Alpha Hydranoid, he briefly teams up with Drago to help him and Dan defeat Druman and Centorrior, the two Pyrus/Darkus hybrid gatekeepers. Shortly afterward, it becomes Alice's Guardian Bakugan, due to Masquerade fading away (along with the negative energy that corrupted them), and its demeanor becomes much less aggressive. He played an important role in the Brawler's quest to defeat Naga and unite Vestroia.
- Ability Cards
- Chaos of the Darkness (Chaos of Darkness): Allows Hydranoid to attack every Bakugan on the field.
- Auragano Revenge (Japanese version: Oregano Murder): Adds 100 Gs to Hydranoid and subtracts 100 Gs from each opponent. (Standard Darkus Ability)
- Merge Shield: Allows Hydranoid to steal all G-power the opponent gained during the battle (Note: the G-Power he steals is not transferred, but added to his current power level).
- Gravity Chamber: Moves all opponents on the battlefield to Hydranoid's card and whoever's power level is lower than his, is defeated.
- Darkus Gravity: Adds another Darkus Bakugan to the battle. (Standard Darkus Ability)
- Fusion Ability Card
- Destruction Buster: Adds 100 Gs to Hydranoid and nullifies the opponent's Gate Card.
Ability Card (Bakugan Video Game)
- Chaos of the Darkness: Adds 200 Gs to Hydranoid.
Hydranoid opens with its head flipping open first, then two parts on its sides extend. The legs have to be opened manually along with the three horns on its neck and head.
Hydranoid was included in Masquerade's Brawler Evolution Pack, a Wal-Mart Exclusive. The Darkus version has 500 Gs and the Pyrus version has 530 Gs.
He was also never released in Japan and was the first American exclusive Bakugan.
- Hydranoid is based off the Hydra, a monster of Greek Mythology, that had the body of a serpent and multiple heads.
- As Alpha Hydranoid/Dual Hydranoid Bakugan form he is able to speak from each head as opposed to ball form when the only one can.
- When Hydranoid first appeared his voice was high and human-like.
- In the trailer for the Bakugan Video Game, Masquerade is seen throwing an Aquos Dual Hydranoid, but it stood as a normal Darkus Hydranoid.
- Hydranoid is missing its horn in the DS version of the Bakugan: Battle Brawler game.
- According to Bakugan.com, all abilities of Hydranoid can be performed by its evolutions.
- In the Bakugan Official Handbook, Dual Hydranoid and Hydranoid's descriptions are merged into one, with an image of the toy form of Dual Hydranoid, due to a toy form of unevolved Hydranoid not existing at that point in time.