The difference in Eren's expressions
I just noticed this little difference between Eren's expression in this single scene in the anime versus the manga and thought it was interesting because I feel like they convey such different emotions:
In the anime, he only scowls coldly, and doesn't seem to show any reaction until Armin calls him a slave.
In the manga, his expression betrays some emotion and (at least to me) it looks like Armin's words are actually getting to him.
(Sidenote: also weird that the anime made Eren look completely unscathed after Armin punched him, when the manga gave him a bloody nose)
There's a few other instances like this where Isayama conveys subtle, complex emotions with the expressions he draws that the anime fails to capture fully. Such as this scene -
Anime: Eren looks rather cold and emotionless when seeing his family
Manga: The sadness in Eren's expression is unmistakable
Thankfully this frame was improved in the Bluray version, but it's a shame it's not the version most people are going to see:
Then there's this scene from when he's watching his child self give Mikasa his scarf:
Which looks so harsh compared to the soft look of longing and sadness he has in the manga:
