I often don't care much for flashbacks, but the two shown over a couple of episodes in this season were really good and saved the entire plot.
I liked how Alina broke character when fear of death took over and made her admit she didn't want to die.
I especially liked how Talulah degenerated into finally betraying her own beliefs and eradicated that village after Alina's death. The dialogue in that part and her train of actions over the course of it felt quite compelling.
Was pure kino.
Almost as good as Geto's breakdown in jjk, and that's up there as being one of the best.

It had its fault, but despite the purple prose and over-convoluted plot threads, it managed to show a few gems here and there. Now, i don't play arknights anymore, but still like to occasionally keep up with it because I'm waiting for Endfields, and really, really enjoy the character designs. As a fan, this could be considered a good game adaptation and is a wholly more favored to what else is out there.

Also, pic related, my favorite two characters, based on their designs.