Well this part raises more questions than it answers.
Eren the secret weapon is interesting enough and some new characters are introduced
This is the battle we can fight… This is the struggle we can undertake.
A daring plan is formed utilizing the power of Eren. As expected this doesn’t turn out as perfect as it sounds (still find Armin his strategies not nearly as brilliant as they are purported to be). We learn of a new commander to humanity, who has some bad ass quotes: To give humanity a chance to survive I’m willing to become a butcher
This Commander Pixis is intriguing but a bit underutilized.
If a powerful non-human entity appeared, humanity would probably unite and stop fighting itself is another philosophical question he raises.
Based on the Covid-19 experiences I wouldn’t count on it.
Overall this volume seems to sing praise of reckless determination and belief, amongst other exemplified in:
That’s right… No matter how many die, we should keep trying!
This makes the overall arch of tension a bit lower, since failure is not an option and singular intent seems enough to achieve miraculous results.