S2·E2 Darkness of the Heart

Tamaki, who was given a strange earring by one of the Orpheus Order's members, Pinochle, challenges Kaito to a Judgment Puzzle in which he must navigate an ever-changing maze. Nonoha deduces that Tamaki's change in personality is the result of her earring, which possesses the same properties as the Orpheus bangle. Tamaki uses the power of the earring to increase her brainpower, but Kaito manages to successfully solve the puzzle. As Kaito reaches Tamaki, her earring breaks, returning her to her senses while the Orpheus Order escapes.