- For the Armored Alliance version, see Nillious (Armored Alliance).
- For the Geogan Rising version, see Nillious (Geogan Rising).
Nillious (ニリアス, Niriasu?) is a two-headed hydra/dragon-like Bakugan that appears in Bakugan Battle Planet. This deadly and powerful Bakugan is owned by Magnus Black and is a rival to Dragonoid.
The double headed Nillious main motive in brawls is to kill - not to win. He does not like fighting as a team with his partner, Nillious is out satisfy only himself. He likes to go rogue. Each head has own personality and ability. Untamable and vicious Magnus has his hands full keeping Nillious in line.
Nillious joins Magnus in his attempt to turn the Awesome Ones' new Bakugan against them, a Darkus Bakugan named Artulean. After Magnus' plan works and he reveals his disguise, Nillious brawls Lightning and Howlkor, but after the rest of the Awesome Ones return, Magnus flees riding on Nillious.
|The information in this section is non-canon. It is purely for entertainment and has no bearing on the plot of Bakugan Battle Planet.
In Tin Pan Alley, while Drago is practicing his abilities on paper targets, Nillious hides behind one of the targets and surprises Drago by attacking with Shadow Breath and Darkus Blast. To expose Nillious, Drago uses Back Draft to incinerate the target.
In Teamwork Makes the Dream Work, Nillious attempts to taunt Drago into a brawl as Drago, Cyndeous, and Gorthion watch up. Instead of listening to Drago's advice and staying hidden, Gorthion steps out and uses Drum Wave, but Nillious uses Reflection and sends the wave back at Gorthion, incapacitating him. After the failed attempt by Gorthion, Cyndeous steps in and uses Volcanic Lance against Nillious, but misses and is taken out by Shadow Breath. Drago then appears, and uses Guard Sphere to trap Nillious in a bubble, leaving him unable to attack further.
Core/Regular Nillious has been seen in all Factions. The Bakugan Ultra version of Nillious is available in Pyrus, Haos, and Darkus. An Aquos version was seen at the 2019 Toy Fair, but was unreleased.
- Nillious bears a strong resemblance to Dual Hydranoid due to both being two-headed dragon Bakugan.
- Additionally, their owners also wore a mask and were Darkus Brawlers.
- Darkus Nillious Ultra is the only Bakugan from Battle Planet to have cards related to it released in every Battle Planet card set, with its Character Card being from Battle Brawlers, its Hyper Evo being from Bakugan Resurgence and its Maximus Evo being from Age of Aurelus.
- For Nillious' Image Gallery, see Nillious (Battle Planet)/Gallery.