First of all, I can't believe you made an online multiplayer game for LD. It's usually not recommended because, as other comments said, most people playing jam games want to play alone. But it's also not recommended because of how hard it is and I, as a programmer, am amazed to see you actually got it to work! Congratulations.
I got pretty far in the game, but couldn't figure out what to do after unlocking the lectern. Using it consumes mana, but nothing seems to be happening.
There are some technical nuances around colliders and graphics (unsolicited tip: disable bilinear filtering for pixel art sprites — you want to use what Unity calls point filtering, it can also be called "nearest neighbor").
In summary: great technical achievement and I like what this could potentially be, but the game is not really intuitive which ruined the experience a bit for me — sorry.