I wanted to add that you can choose which quests you want to occur in each run!
There are these screens with a lever at the start of floors 1, 5, and 9. They are in the top left corner and can be hard to spot.
Here is what it looks like:
https://imgur.com/a/PycVE0jYou can click the lever, and depending on which icon is present on the screen, it will determine which quest shows up on the next floor.
For each of those 3 floors, here is the list of which icon you'll want so that you can try to complete that quest:
FLOOR 1 (quest will appear on FLOOR 2):Egghead icon (3 circles) -> Zombie Lover quest
OR Knowledge is Power quest
- To unlock zombie lover, don't return to the scientist. But if you do, you unlock knowledge is power
Newbie icon (looks like a person) -> Assemble a Meganewbie quest
Tanks icon (shield) -> Impossible Cube quest
Healer icon (+ sign) -> The Return of a Rat quest
FLOOR 5 (quest will appear on FLOOR 6):Trickster icon (arrow) -> Campaigning quest
Mage icon (eye) -> To the Moon and Back quest
Cultist icon (tentacles) -> Catch Jonathan_tostar quest
FLOOR 9 (quest will appear on FLOOR 10):Fighter icon (yin yang symbol??) -> Feed a God quest
Fencer icon (sword) -> Holy Vengeance quest
Thrower icon (target) -> Great Flight quest
I believe those are all of the quests, please do let me know if I missed any.