Attack on Titan (AoT) is an anime based on the manga created by Hajime Isayama. The story takes place in a land of three circular walls, the smaller ones inside the larger ones. Man-eating creatures called titans live outside the walls, waiting for a chance to get inside. When a colossal titan destroys the first wall, 20% of humanity went along with it. The human military is broken into three sections: The Military Police, Garrison Regiment, and Survey Corps. Plot twists, betrayals, and main character deaths are very common. Titan shifters, humans that can transform into titans at will and vice versa, are very rare and have their own unique powers; some choose to help humanity while others choose to destroy them.