The heroes travel to Japan to search for information on the Oni, and are soon fighting the villains for the second Oni Mask.
- Back-to-Back Badasses: Jackie and Will.
- Color-Coded Wizardry: When Ratso wears the Oni Mask, his Dark Chi Warrior markings and the aura of his hammer change from blue to black.
- Crazy-Prepared: Like in canon, the vault at Section 13 containing the Oni Masks is protected with an onion-powered anti-Oni ward to keep Tarakudo out.
- Don't Explain the Joke: When Tarakudo makes a joke that Hay Lin finds funny, she explains it.
- Eviler than Thou: When Cedric tries to tell off Ratso, who's wearing an Oni Mask, the latter instead intimidates the former under the Oni General's influence.
- Jedi Mind Trick: The trope name is dropped by Yan Lin when she reveals that she used a chi spell to convince the parents of the Guardians and Alchemy that they were just having a sleepover when they're really in Tokyo researching the Oni.
- Jerkass Has a Point: Cornelia is a bit too happy about Uncle's 10-Minute Retirement for Will's liking, but when she defends herself by saying that Uncle hasn't been very useful in the quest for the Oni Masks, Caleb agrees with her by reasoning (in a more polite way) that Uncle isn't best suited for this particular task due to his lack of knowledge regarding Japanese myths, and that when on Rebellion missions, it's standard procedure to send members whose skills are ill-suited to the mission in question back to the base.
- Katanas Are Just Better: Caleb picks up a katana during the fight in the museum. It will go on to be his weapon for the rest of the series.
- 10-Minute Retirement: Like in canon, Uncle leaves the team during the search for the Hanafuda cards due to believing that his lack of knowledge of Japanese lore and magic is only a hinderance. But whereas in canon he comes back on his own, here it takes a mini Rousing Speech from Yan Lin to encourage him to do so.
