The Skull Sorcerer is the seventh episode of the thirteenth season of Ninjago and the 151st episode overall. It aired first in English on July 13, 2020, in Australia. It aired in the US on October 4, 2020, paired up with "The Real Fall."
Back at the Kingdom of Shintaro, Vania is wondering what if she should save the ninja or hope that they are alright and hopefully they can save themselves. She asks Chompy, but the dragon believes she should relax.
However, Cole is in deep trouble as he hangs off a branch overlooking a deep abyss below, while screaming for help. Cole tries to come up with a plan and spots a skeleton holding a hook. Without notice, the branch breaks, but Cole is able to hang onto the skeleton's legs. He then lassoses the hook onto a rock, but the skeleton breaks as well. Cole tries to climb using the hook and rope, but the rock also breaks. Luckily, he hangs onto a cliff and screams for help.
Suddenly, he encounters Dire Bats and one of them picks Cole up. The other one tries to clasp Cole, but it results in Cole falling until a third Dire Bat takes him and begins flying away from the group. While being chased, Cole uses his Earth Punch to slow down the other Dire Bats. He then is able to break free from the Dire Bat who had Cole and runs to a cave. Unexpectedly, the Dire Bat retreats and Cole brags on how superior his abilities are, but he runs into a giant spider.
The spider comes down from its web and tries to eat Cole. At first, Cole is able to hold up until the spider shoots webs at Cole's hand, and eventually his entire body. Facing certain doom, Vania and Chompy came in to fight the spider. Chompy tries to give aid, but the spider simply swipes the small dragon. Vania then hurls her spear at the spider, but the spider defect it. Vania gets frustrated at the spider, and unknowing to Vania, Chompy turns into a gigantic dragon, and the spider flees. Cole tells Vania about Chompy, but Vania thought he was overthinking it.
Back at the kingdom, Wu enjoys his cup of tea as well as the sweet smell of flowers blossoming. He wishes to enjoy the moment with the ninja, but quickly turns around to find Cole and Vania out of the mines. Wu is flustered at Vania for not keeping her promise, and Vania apologizes to Wu. While this is all going on, Chompy climbs on Wu, and questions whose dragon it is. Vania replies that the dragon is her's and tells Chompy to stop eating the flowers. Cole then tells Wu about the Skull Sorcerer and the Re-Awakened, so they immediately head to Vangelis to warn him.
Wu, Vania, Cole, and Chompy interrupt Vangelis to tell him everything they witness. Once again, Vangelis criticizes Vania for going to the mines, as he was trying to protect her. However, when Cole incorrectly mentions that the Skull Sorcerer having a red skull, Vangelis corrects him by revealing the skull. Suddenly, he transforms into the Skull Sorcerer, which shocks everyone.
The Skull Sorcerer claims in order to keep the Sky Folk's city intact, he forces the Munce and Geckles to mine Vengestone for his customer, who would later pay Vangelis to keep the kingdom. Vania cannot believe it, and Cole shouts his reign will end, so Vangelis throws the Skull of Hazza D'ur at Wu and Cole. Chompy then tries to attack, but Vangelis hits the little dragon. Vangelis then activates his trap door to drop Cole and Wu into the pit. Vania decides to grab a pair of Shintaro wings, and Vangelis threatens Vania saying if she were to jump, he would no longer considered her to be his daughter. Vania ignores her father and still jumps to go after Cole and Wu.
According to Bragi Schut, the directors haven't established whether Cole is colorblind or not based on his failing to recognize the colors of the Skull of Hazza D'ur. However, Schut said "I wouldn’t be surprised if he was."
In this episode, Vangelis is revealed to be the Skull Sorcerer.
Vangelis' identity as the Skull Sorcerer was foreshadowed in "Into the Dark" and "The Worst Rescue Ever," when he forbid the ninja into going to the Dungeons of Shintaro by saying that the things there "should not be disturbed," which was referring to himself and his underground mining operation.
As of this episode, the ninja have retained their post-movie designs longer than their original designs. While they retained their original designs for 76 episodes (counting the pilot episodes), this episode marks the 77th appearance of their post-movie designs.
However, when taking episode length into account, their old designs have been used longer.