The Endless Ocean (also known as the Endless Sea) is the sea that surrounds every island and landmass in Ninjago.
Lord Garmadon and the four remaining Serpentine generals fly over the Endless Ocean to try to find the Dark Island. After searching all day, Skales pushes Garmadon into the ocean so he can become the new Serpentine leader.
- The Endless Sea was what truly defeated the antagonists of the fourth and fifth seasons of Ninjago: the Anacondrai Cultists and the Ghost Warriors.
- The Cultists were drowned.
- The Ghost Warriors were dissolved.
- Deepstone is found and mined at the bottom of the ocean.