S1·E21 Holly Land's Vanish

Karin attempts to keep Medusa under control but the building she's in collapses and she is forced to escape. Kuniko, Kunihito and Momoko arrive just in time to join in the rescue efforts to extract surviving Akihabara citizens. Kuniko talks some sense into a despondent Karin and join forces to prevent Medusa from causing the end of the world. They find the otaku owners, who have survived, to aid them in their operation. Using an independent network provided by the otakus, Karin hacks into the orbital communications satellite Icarus to send it descending onto Medusa's location. However, the celebrations are short-lived, as Medusa remains alive, tapping into the world military networks to prepare to launch warheads and create a nuclear winter. Karin reveals to Kuniko and Kunihito about their statuses as successors to Atlas. In order to use the Zeus AI against Medusa, they have to prevent Mikuni from becoming successor as the control system will only obey her commands. Mikuni ascends a long flight of stairs to Ryoko, who welcomes her to the Endless Forest.