Ah! Yes, I think one of the things we missed adding was a pause menu during the game where you could exit or view the controls. I'll go ahead and update the game page with the mouse + keyboard controls.
We had initially made the Lich much tougher (because your abilities can a bit overpowered when used in certain ways) but we decided to tone him down and it sounds like he's in the right place now.
Thank you for the feedback and playing our game!