Based on the activity you saw on the walls and the glimpse Arc briefly had over it it is estimated that going up in daylight would be far riskier so you decide to wait. Keeping the door open only a crack for some fresh air, augmented by a magical fan the Kaarik cobbles together in a couple of minutes, you settle down to wait.
As you rest you look over the items recovered from the pit and between Kaaric and Skeeve are able to identify their basic functionality. The book contains several chapters discussing magics with each containing a single spell while the wand contains only a pittance of it's previous might though it may be repairable.
[ +- ] Dissertation on Magics
Alarm : Designate an area (zone) and you will be mentally alerted any time a small or larger creature enters or leaves. This spell lasts 12 hours.
Create Homunculus : This spell has special material requirements that must be crafted by an alchemist. Once these have been procured you can cast this spell and gain a familiar bound in flesh. It can interact with physical objects but when slain is gone forever.
Wall of Light: Create a glowing opaque wall of light in the shape of a strait or curved wall 20'x20 or 10'x40'). Any that pass through it take 1 damage and must save of be blind until the end of their next round.
Flame Arrows: 6 arrows are summoned overhead. Each time you perform another action you can launch one of these at a target of your choice (no action, basic test to hit, 1 damage).
[ +- ] Wand of Compulsion
By pointing the wand at a creature within 30 feet the bearer can send messages mentally and it will be understood if they know at least one language. This communication is one-way only. Damaged enchantment that no longer works: Thrice per day the wielder can compel a target within range to save or act as commanded for 1 round. (save with advantage if the command is self harmful)
Geis
Popping out of the pack the ghostly kobold wanders off to explore the sewers and returns after confirming that they were standard for the city.
Typically the sewer crawlers would not be that large and aggressive. I'm guessing they interbred with warborn monstrosities He chats a bit with you while you wait and pulls out some dice, proposing a game with wagers to while away the time while you wait.
If you want to play propose your bet up to 10 gold. Bets can be against just Geis or an open round with all participants contributing to the pot, winner take all based on their bet. (you bet 1 gold you get 1 gold per player) Geis will roll last.
Roll 5d6, up to 3 times by editing your post. Indicate in the successive rolls which dice are bring rerolled. set the visibility to "HIDE ROLL RESULT", and use yahtzee rules scoring, with everything but the "Chance" doubled on value, to determine the winner
Example below. Result 3,4,3,4,1 = chance= 15 or 2x4's = 16
