In my opinion it was a totally disappointing arc for what was promised
The first wall was pretty decent if it felt like a war and the various fronts were handled well sure I have my issues with Lyborick's plan which seems pretty stupid to me Canhong and Evankhell surviving a bullet to the head but he had big moments like Karaka and Baam VS Kallavan, Evankhell annihilating a squad and White absorbing the souls of the battlefield
The whole arc decays enormously with the start of the Cat Tower, which in my opinion was a big mistake.
This part was too long and didn't end on the right time (before Traumerei arrival), there was a lot of false tension and irrelevant fights
It had good moments, like some flashbacks of minor villains, but they were too many and interrupted the main story.
White and Baam's battle was pretty good, sure, I didn't like Aria's resurrection or Khun and Rak's interference, but the atmosphere managed to create tension when Baam was being cornered with no escape.
I liked Yama's battle but not having had a victory before that defeat felt a bit humiliating, if he had fought a Beastkin (Robby?) or a BH before and used his FT to stop postponing it my opinion would highly improve
Everything Evankhell did was irrelevant and a waste of time.
Same with Kallavan, in my opinion he should have faced Baam and closed his character arc in a good way before becoming irrelevant as an enemy
On the matter of Traumerei, I hope that SIU doesn't use (again) the excuse that the other FHs also see the Regulars as insignificant to justify their inefficiency and this is an isolated case.
His performance against Yama and Yasratcha left a lot to be desired, of course, he did not move for most of the time and he killed Yasratcha as soon as he got serious, but allowing everyone to do what they want in his presence took away the impact and seriousness of it, Kallavan imposed more respect than an FH in his moment
The fact that his Shinwonryuu didn't kill anyone important, after saying that it was a "calamity" and only killed his own soldiers and destroyed his own base is an unnecessary humiliation for him.
About Baam, his response to Traumerei was completely stupid and hurt the arc's closing a lot.
I think this arc could have worked much better with minor changes, the concept was pretty good, but it left a lot of unresolved plots to finish it in a hurry which felt very disappointing