The second season of Attack on Titan based on Hajime Isayama's manga was completed on Saturday June 18, revealing good news. At the end of the 12th and last episode, it was announced that the 3rd season of the anime will be released in 2018. The announcement was also confirmed on the official Attack on Titan account on Twitter.

The second season of Attack on Titan premiered on April 1 and ended with 12 episodes, while the first 25-episode season was released in April 2014.

Source: animenewsnetwork.com