|“And finally, the reason for your protection; the Mask of Deception.”|
The Oni Mask of Deception was one of the three Oni Masks. When worn, it granted the user the ability of telekinesis, allowing the user to move objects with the power of their thoughts.
At some point in time, the Oni Mask of Deception and the other Oni Masks were created by the Oni in the Realm of Oni and Dragons and brought to the realm of Ninjago. It would eventually fall into the possession of the Royal Family and remained in the Royal Palace.
As predicted, the Sons of Garmadon attack the Royal Palace in hopes of stealing the Oni Mask of Deception. While Ultra Violet and several other Sons of Garmadon members fend off against the defending Royal Guards, Mr. E rides his bike through the palace and eventually finds where the mask is located. However, the Ninja corner him in front of the mask's display case. Unknown to the Ninja, Mr. E brought along the Oni Mask of Vengeance and puts it on, where it gives Mr. E two additional arms and swords. Mr. E fights off the Ninja, eventually knocking them down after utilizing the mask's power to use Jay's Lightning against them. As Mr. E claims the Oni Mask of Deception, Kai, in a last-ditch attempt to stop him, blasts a fireball at him, which ultimately shatters the Oni Mask of Deception in his hands.
However, it is revealed that the Oni Mask of Deception that was on display was a fake; Hutchins had hidden the real mask in the vaults below the palace and tasks Lloyd and Harumi with fleeing with it. However, they are soon chased down by Ultra Violet and a few Sons of Garmadon members, who manage to "knock" it out of Harumi's hands and claim it before Lloyd and Harumi can.
Killow uses the Oni Mask of Deception to lift rocks into the air in attempt to crush Zane during the bike race after finding out he was a spy, trying to make him lose the race. However, Zane manages to dodge all of his attacks, forcing Killow to escape with the mask while Mr. E fights Zane.
Killow uses the Oni Mask of Deception's telekinetic powers to create a bridge of rocks over a trench for the Sons of Garmadon to cross in order to reach the crashed Destiny's Bounty. After reaching the Bounty, Killow and Mr. E both put on the Oni Masks of Deception and Vengeance on, respectively, when confronting the Ninja.
Killow uses the Oni Mask of Deception during the Ninja and the Sons of Garmadon's battle with the Sea Monster.
Killow uses the Oni Mask of Deception to cause carnage against the Ninjago police force during their attack on the Royal Palace, which was taken over by the Sons of Garmadon and coverted into the Temple of Resurrection. The Oni Mask of Deception would later be used in the resurrection ritual with the other two masks. However, the Ninja would stop the ritual before it could be complete. The Ninjago police force soon arrives, arresting the Sons of Garmadon and presumably confiscating the masks. It is possible that the Sons of Garmadon later recovered the Oni Masks.
During the Sons of Garmadon's surprise attack on the Resistance's headquarters, Killow utilized the Oni Mask and Deception, effectively using its powers along with Harumi using the Oni Mask of Hatred to help overpower the Elemental Masters.
As Skylor gains control over the Colossus, a small Sons of Garmadon team lead by Ultra Violet and Killow arrive in the streets to apprehend the remaining members of the Resistance. After Ultra Violet was throwing across the city by the Colossus, Killow proceeds to put on the Oni Mask of Deception and uses its telekinetic powers to levitate three cars in order to damage the Colossus. However, it simple pushes away the cars, causing them to fall and pin Killow onto the ground, knocking off the mask from his face. As he desperately reached out for it and grabbed it in his hand, the mask cracked and fell apart, destroying it.
- The Oni Mask of Deception is the only mask that doesn't alter the user's physical appearance.
- In the sets, the Oni Mask of Deception's print is erroneously mirrored.
- During the ritual in "Dread on Arrival," the Oni Mask of Deception is referred to as "Clotho-decer" by Harumi.
- The Oni Mask of Deception has the most appearances out of the three Oni Masks.