No Regrets is a Levi prequel set before the events of Attack on Titan. Again, watch that after the first season. The only other OADs are the Annie-centric Wall Sina two-parter and a surreal Mikasa ...

Utilizing a healthy dose of CGI and 2D animation ... Isayama's widely popular manga, Attack on Titan is a dark fantasy anime set in a world where humanity lives behind walls to protect themselves ...