LEGO 853866 Oni Villains Battle Pack is a Ninjago March of the Oni set released in 2019, containing 36 pieces and 3 minifigures. It includes The Omega, the leader of the Oni, along with two Oni warriors, with character details such as horn elements. The set ties into the March of the Oni storyline from Ninjago: Masters of Spinjitzu, in which the Oni serve as the primary antagonists. It was retired in February 2021 with a lifespan of 25 months.

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