Everyone in the Attack On Titan universe is irrevocably changed throughout the series, experiencing hardship and loss around every turn, and having their hopes crushed even further anytime it looks like there's a shred of hope. This is especially true for Eren Yeager, who's set on a path of revenge the day his mother's killed by a Titan, and who ends up inciting the Rumbling and wiping out all but twenty percent of the entirety of Earth's human population.
Source：https://www.cbr.com/attack-on-titan-eren-yeager-most-iconic-moments/
