The Tomb of the First Spinjitzu Master is the final resting place of the First Spinjitzu Master, it is underwater in the Endless Sea. The First Spinjitzu Master died peacefully there holding the Realm Crystal.
At some point in Ninjago's ancient past, the First Spinjitzu Master created a tomb underwater where he would lay in his eternal rest. He then engraved three hints to the tomb's location on his staff, which he passed down to his younger son, Wu.
After reaching the tomb, the ninja stand before a statue of the First Spinjitzu Master outside the entrance. Upon realizing they would be entering the tomb of the creator of all of Ninjago, they slowly moved forward. They entered a circular room with sixteen doors, all with patterns. This was the First Test; they had to pick the correct door. With the help from P.I.X.A.L., Zane figured out the patterns on the door is a zoetrope and does Spinjitzu to get an image of a Yin Yang and points to the door with the corresponding image on top - the door they came in through.
As the ninja entered the room with the Second Test, they saw a golden staff at the end of the room. They try desperately to reach the golden staff while avoiding any traps they trigger. After failing multiple times, Cole realized they weren't meant to obtain the staff in the first place and jumps through the hole in the floor caused by the traps.
After jumping down, the ninja were taken on a rollercoaster of ice slides, bumping and bashing them about. They soon reached the Final Test - a Maze. As the team look for a way out, they notice that their reflections are of their older selves. However, Cole cannot see anything. While trying to find his reflection, Cole finds Morro and they battle him using icicles. Kai eventually traps him, and they continue the test. They noticed a bright light below them and start to dig.
The ninja fall down into the final cave. There in front of them, was the First Spinjitzu Master, holding the Realm Crystal. The ninja kneel in respect before Zane carefully removes the Realm Crystal. As they stare at it in awe, Morro shows up and threatens the ninja to hand over the Crystal or he'll drown Lloyd. Because he's not possessing Lloyd anymore, the ninja's elemental powers return, but were weak due to Lloyd's condition. After a brief discussion, Kai heats up the crystal and tosses it to Morro, who burns and quickly drops it in the river, along with Lloyd. They once again have another battle. While the ninja save Lloyd, Morro obtains the crystal and leaves the tomb. The ninja soon make it out with Lloyd and with their Elemental Powers restored, they're ready for the battle at Stiix.
- 52. "Grave Danger"
- 3. "Legendary Places"
- Ninjago Possession (non-canon)
- The First Spinjitzu Master's staff is still in the Tomb since it was never removed by the ninja or Morro.