Two minor bugs and one thing that I don't think is a bug, but am reporting just in case:
The bugs: Green slimes don't appear in the library when present, or rather, they appear and as counted as blue slimes, and the dragon always shows as having 11 power in the library, even on deeper floors.
Possible Bugs, Probably intentional: XP required to level never increases past 30 on level ups, and max HP never increases past 23 on level ups. (e.g. if a player requires 30 xp to level up and does so, they will fully heal and possibly gain 1 max HP (if an odd level, and max HP is below 23) but will still require 30 xp to reach the next level; if a player has 23 max HP and levels up, they will fully heal, but max HP will never increase). Here's a merchant that reached this stage on Floor 3 and again on Floor 4.