Mystake
Mystake was an Oni disguised as an elderly woman who owned a tea shop within Ninjago City . Mystake once lived in the Realm of Oni and Dragons alongside her fellow Oni, and was one of the three powerful Oni warlords who wielded the Oni Masks , specifically the Oni Mask of Deception . [ 1 ] When the First Spinjitzu Master fled the realm, Mystake went after him with her peers to either bring him back to the First Realm as an ally or to kill him should he refuse their offer, but after seeing the beauty in the realm he created, she changed her ways. Over the years, Mystake witnessed much of Ninjago 's history, including the end of the Serpentine War . She was acquainted with Wu , a son of the First Spinjitzu Master, and occasionally provided him and others with various types of tea with special powers. . When the Sons of Garmadon sought to resurrect Lord Garmadon , Mystake provided the ninja with knowledge about the Oni and Dragons . She later helped save Lloyd after his nearly-fatal battle with his father and motivated him to lead the Resistance after his friends were seemingly killed. During an attempt to seize Garmadon's power , Mystake revealed her true Oni form and battled the Dark Lord. She was ultimately overpowered and killed, though her actions helped the ninja claim victory. .