The Serpentine are the central antagonistic faction of LEGO's Ninjago theme, including sets, the cartoon, and other spin-offs. They are an ancient race of reptilian humanoids who were once the dominant species of Ninjago. They were the primary enemies during Ninjago's 2012 theme run, replacing the Skulkin in 2011 and being replaced by the Stone Army in 2013.
In the ongoing cartoon titled LEGO Ninjago: Masters of Spinjitzu, the Serpentine were a recurring character faction, and served as the main antagonistic faction of Season 1: Rise of the Snakes, as the secondary antagonistic faction of Season 2: Legacy of the Green Ninja (serving as the main antagonistic faction of the first half, and as a minor antagonistic faction in the second half), as a minor protagonistic faction in Season 3: Rebooted, as a supporting protagonistic faction in Season 4: The Tournament of Elements, as the main antagonistic faction of Season 7: The Hands of Time (through only the Vermillion Warriors), and as the main antagonistic faction of Season 11: Secrets of the Forbidden Spinjitzu (through only the Pyro Vipers).
They warred with each other for centuries until the people of Ninjago rose up (likely with the aid of the First Spinjitzu Master) and locked them away in five separate tombs, one for each tribe (Anacondrai, Hypnobrai, Fangpyre, Constrictai, and Venomari). Centuries later, they were released by Lloyd Garmadon and Pythor.
The Serpentine have an undefined connection to the Great Devourer, worshipping it as an all-powerful god and ruler. They formerly believed that the Devourer could have been used as the ultimate weapon for ruling Ninjago and getting revenge on its current inhabitants, but they saw him failing.
- King Mambo V - First Snake King
- Queen Aspheera - First Snake Queen
- Arcturus - Second Snake King
- Pythor P. Chumsworth - Third Snake King
- Lord Garmadon - Fourth Snake King
- Skales - Fifth Snake King
- Arcturus - General
- Five Anacondrai Generals
- Pythor P. Chumsworth - Informal General
- Anacondrai Warriors
- Anacondrai Serpent
- Skales - General (Former Warrior)
- Slithraa - Warrior (Former General)
- Mezmo - Soldier
- Rattla - Scout
- Selma - Soldier
- Skales Jr. - Scout
- Fangtom - General
- Fangdam - Warrior
- Fang-Suei - Soldier
- Snappa - Scout
- Skalidor - General
- Bytar - Warrior
- Chokun - Soldier
- Snike - Scout
- Acidicus - General
- Lizaru - Warrior
- Spitta - Soldier
- Lasha - Scout
- General-turned-Supreme Commander Machia
- Commander Raggmunk
- Commander Blunk
- King Mambo V
- King Mambo V's Advisor
- Queen Aspheera
- Servant Char
- Pyro Destroyers
- Pyro Slayers
- Pyro Whippers
- Fire Fang
- Elemental Cobras
- Anacondrai - They are purple Serpentine capable of turning invisible. They were once the most powerful Serpentine of all time but are now extinct. (Except for Pythor.)
- Hypnobrai - They are blue Serpentine with red eyes that are capable of hypnotizing anyone.
- Fangpyre - They are red Serpentine with venom that can turn any human or machine into living snakes.
- Constrictai - They are black Serpentine that are capable of squeezing their victims and and are very good at digging.
- Venomari - They are green Serpentine with venom that can make their victims see hallucinations.
- Vermillion - The first-generation progeny of the Great Devourer, appearing as masses of snakes that can merge into humanoid forms.
- Pyro Vipers - An ancient tribe of Serpentine that lived as Egyptian-type characters, and can absorb any source of fire or lava that they please.