Aerisi has a spellbook in her possession (pg84) but you are right about the others. I have described other NPCs that cast Wizard spells (eg Lizzie Calderos in the Fire Temple) as carrying spellbooks, which contain the spells that NPC had prepared. I guess the NPC should probably have more spells...
Hey Nailen, welcome to ENWorld.
I have been DMing this campaign for 18 months, and here's my 2cp.
The PotA guides from Power Score Blog and Mike Shea (Sly Flourish) recommended this as well. (Both great resources for running this adventure if you haven't checked them out already.) Personally...
You can listen for yourself - they did a demo during the announcement on Stream of Annihilation:
https://youtu.be/yD0pr7uOCF0?t=12m45s
I've even skipped past nearly 13 minutes of the other fluff for you. :)
It's going to be neutral pronunciations
I'm going to blow your mind...
My very first post to these forums pointed out that the link between Acquisitions Inc and Force Grey was... the Rod of Seven Parts.
You can't find it because it was lost in the Great Data Loss of 2016. I'm not saying I had anything to do with that data loss, no...
Todd Kenreck has a YouTube channel called Dungeon Life and one of the videos is an interview with WotC concept artists Shawn Wood and Richard Whitters.
There were lots of concept pieces shown, mainly from OotA, VGtM and SKT. But two images in particular grabbed my attention, one labelled...
Opportunity attacks can only be made against creatures you can see (no ability check involved):
Spell descriptions may specify targets that you can see and in those cases are also affected by the Blinded condition.
Give the player the option of which to use - they will generally pick the one with the better bonus. Stacking bonuses doesn't play well with the Bounded Accuracy principle that 5e is built upon.