Some folks seem to be let down by the ending being "anti-climatic" but from how I see it it was never meant to be like that, given the build-up in more than 40 chapters and tons of hints, Kasen is definitely up to something the moment she first met Reimu at the shrine, but not with any malice (how she always treats people around her with critical thinking). The whole scheme that Kasen came up with was solely for the purpose of seeking her own "death" or other personality or whatever it is, nothing something epic or complicated with a true malicious intent behind bla bla that you normally see in mysterious trope, so to me this kind of plot is just Touhou-sque.
I really enjoy this chapter from top to bottom, how Reimu still gets ridiculed in the midst of the combat, or how Tenshi finally got some moment to redeem herself, or how Kasen's true motive was finally revealed, and lastly the final scene with Kasen having a toast with her old-self, which was very impactful and thus solidifies her position as my new favorite Touhou character for her cool, calm, and cute nature.
Overall, this manga has been a really good ride, even though the slice of life contents take up lots of panel time I didn't mind all that, but still prefer the story leaning toward the direction of the last 3 chapters more due to the intense atmosphere and hype it gives off, but whatever, it's Touhou so what can I expect. Just wish that other characters like Aya got some more moment since she's been hinted to play quite a role in the whole business behind Gensokyo. At any case, the most satisfying thing so far about this manga is how I got to see Reimu getting fodderized in every aspect (just a bad hobby of mine to enjoy seeing MC getting trashed and ZUN did not disappoint).
Thanks Alpha Beta Kappa for scanlating this manga and hope they'll keep doing more Touhou work if there's any to come in the future.