An Hacked Ritsu in Assassination Classroom (Season 2)

This is where Ritsu, the A.I. girl got hacked by the Reaper who was waiting for the students of Class 3-E (the main cast of the series) to stop him in order to save Irina from being bound and gagged inside a dungeon. The Reaper lured the students into his trap at a fortress, but they attempt to escape and find Irina while the other students are taken down by The Reaper one by one, and even Nagisa was thwarted by his clap stunner.