Shingeki no Kyojin

For more than a century, humanity has lived behind three enormous walls that protect it from Titans, humanoid creatures that devour people for no understood reason. To Eren Yeager, that safety has always felt like a prison, until a Titan taller than the wall smashes open Shiganshina's gate and the invasion kills his mother before his eyes. Eren vows to destroy every Titan and enters the military alongside Mikasa and Armin, but training cannot prepare them for the scale of what waits outside. Their first battles reveal phenomena that overturn everything they thought they knew about the Titans and about Eren himself, making the question of how this world came to exist as dangerous as simply surviving it.