Funny take on the theme !
I like that you put mouse aiming for this makes the controls real smooth, one thing i'd say though is that there's a bit of lack of feedback when you hit the ennemies and when they are converted, maybe have a little sound cue and visual effect to clearly indicate the change. I also had a bit of a visual glitch, where sometimes when you move you see a gap between tiles for like a microsecond, i think this is still more of a godot issue in general so not sure if you can do much about it :(
Still i like that you made it that ennemies join you each one you defeat, and that you have a progressively bigger mob following you and throwing books around :D
had a fun time, good job dude !