Great Devourer

The Great Devourer was a monstrous snake that was created by the Overlord and worshipped by the Serpentine as a god, believed to consume all of creation if left unchecked. According to legend, she could only be unleashed if the Serpentine tribes united as one and found the four silver Fangblades.

When Lloyd freed Pythor, the Anacondrai began scheming to awaken the Devourer by uniting the Serpentine and finding the Fangblades. Following a series of battles with the Ninja, the Fangblades were obtained and Pythor unleashed the Devourer from The Lost City of Ouroboros, after which she consumed Wu and Pythor before heading into Ninjago City to wreak havoc. The Ninja battled the Great Devourer, which proved to be a dangerous adversary, until Garmadonoffered to destroy the beast by combining the Golden Weapons. Reluctantly, the Ninja gave him the weapons, and Garmadon killed the beast.

Despite all, the demise of the Devourer would only create further conflicts. The Devourer's venom revived the Stone Army and Krux used eggs from the beast to breed an army of Vermillion warriors. Needless to say, the massive serpent had a tremendous influence on the future of Ninjago.

Abilities
The Great Devourer had an insatiable appetite and the ability to consume anything that it came across. Whenever it consumed something, it grew larger and more powerful—the Ninja noticed that it would have been truly unstoppable if allowed to consume the bustling metropolis of Ninjago City.

In combat, the Great Devourer normally used its tremendous size and nigh-invulnerability to its advantage, attempting to swallow anything in its path and smashing opponents with its spiked tail. Its venom was capable of bringing inanimate objects to life and could corrupt even the purest individuals into wrathful megalomaniacs against their will, such as the case of Garmadon.

Additionally, it seemed to display a sense of tactical thought, tricking both the Ninja and the Ultra Dragon into thinking they had either defeated or escaped it, only to suddenly ambush them when their guard was lowered. Despite its massive size, it was also incredibly fast and had the ability to burrow through the ground with ease.

The Great Devourer only displayed two real weaknesses over the course of the show. Like the Serpentine, it appears to be intolerant of the Sacred Flute's music, to the point of physical pain. It also had a small weak spot on top of its head—if it took a particularly powerful blow to this point, it would result in its death, as evidenced when Garmadon used the Golden Weapons to finally destroy it once and for all.