Questions for Impuritas Civitatis ( SPOILERS )

[The Whispering Penis]

I am at The Invitation part and is it okay to proceed without finishing the abnormality stages? Will not doing all of them lock me out of endings?

Any advise to better prep for the fights before going in since I won't be able to farm for books?

[Star/AntianSlider]

Yes you will be locked out of endings, finish all the abnormality fights before the endgame.

[Dice_24K]

Once you being, you won't be allowed to replay old receptions, you don't be able to do any abno battles/realizations, and you will not be able to BURN ANY BOOKS. That last one is a real sticking point for me since I like to hoard a bunch of books at a time.

Thing is, you can quit out and go back to the post-Hana Association Battle at any time, buuuuuuuuuuut you will start over.

To avoid spoilers, abnormality battles/realizations are critical path, not side content (side content is the general invitations) and not doing them will lock you out of the best ending.

Advice for preparing for the fights: you're gonna need to prep up 4 floors at one time, at the most. Don't prepare your entire library unless you want to do a challenge run (called a "10/10 Lockout"). If you hate making build after build, check out my Impuritas Guide (here, on Steam) for builds, I have way more than 20 different builds and use whatever you want from it.