Author Hajime Isayama announced in the 14th Volume of Attack on Titan (Shingeki no Kyojin) that the spin-off Attack on Titan: No Regrets (Shingeki no Kyojin Gaiden: Kuinaki Sentaku) will get its animated version, that is, an OVA.
This animation will arrive in two new original DVDs that will be packaged with the 15 and 16 main manga on December 9, 2014 and April 9, 2015 , respectively. Artist Hikaru Suruga and writer Gan Sunaaku launched the manga spin-off in the Kodansha magazine last year, and Kodansha Comics where it was published in North America . Kodansha Comics describes the story:
The story revolves around the past of Corporal Levi Rivaille , the leader of the Special Operations Squad and one of humanity's greatest hopes. “How will a bandit from the royal capital be able to move forward as humanity’s strongest being?”
The team and cast of the Shingeki anime at Kyojin were confirmed in this animation.
Via: ANN