The former has 16 chapters while the latter has 20 chapters. Depending on the pacing of the story in the manga, these two story arcs will likely make up “Attack on Titan” Season 2.
“Clash of the Titans” and “The Uprising” are actually eventful story arcs, and they will deliver both story development and larger-than-life action sequences in the anime.
The former will see the 104th Training Corps deal with Titans that breached the Wall Rose seemingly out of nowhere as another danger brews.
The latter chronicles the kidnapping of Eren and Historia, which was an indirect cause of a character’s death. It also leads to more information about the Reiss family.
If “Attack on Titan” Season 2 will have 25 episodes once more, it looks like the anime will save the much more revealing parts of the manga for another season.
Those who have been following the manga know that Isayama dropped some major revelations about humanity’s existence, what lies beyond the walls, and the source of the Titan’s power and who held it first.
These new chapters are, of course, part of the ongoing “Return to Shiganshina” story arc, which clears things up about the mystery of the Titans.