Blue Exorcist - Season 1 - Eps 12: A Game of Tag
The Exwires are tasked to look for the ghost of a child that is haunting Mephisto Pheles' amusement park. Rin and Shiemi manage to find the ghost first, but Shiemi ends up chasing it by herself while Amaimon, a higher demon and another son of Satan, steals Rin's sword and forces Rin to fight with him. Mean while another exorcist comes to defend him, and it is reveal to be an old friend of Rin's brother.
About Blue Exorcist

Title: Blue Exorcist
First Air Date: 2011-04-17
Last Air Date: 2025-03-23
Status: Ended
Rating: 7.9/10 (from 464 votes)
Language: JA
Seasons: 6
Total Episodes: 73
Network: MBS TBS CBC Gunma TV Tokyo MX BS11 Tochigi TV i-Television SBS
Genres: Animation, Sci-Fi & Fantasy, Mystery, Action & Adventure
Production Companies: A-1 Pictures, Aniplex, Shueisha, movic, dentsu, MBS
Synopsis
Humans live in the world of Assiah, demons in Gehenna. The two dimensions are not meant to interfere with each other, but demons still possess creatures in Assiah in spite of this. The humans who can fight these demons are known as exorcists. Rin Okumura is a boy who bears the curse of being Satan's illegitimate son. His foster father sacrificed himself to save him from demons. To avenge his foster father's death as well as to prove himself, Rin decides to follow the path of an exorcist and defeat his own father, Satan. To hone his raw skills, Rin enters True Cross Academy to train with other exorcist candidates.
Cast

Hiroshi Kamiya
Mephisto Pheles (voice)