An important first lesson for GameMaker users: never package your game as an installer, ESPECIALLY for jam games. People download these by the dozen and usually delete them afterwards. Installers make the whole process so much more cumbersome, and I've noticed that even in my "commercial" games nobody uses installers. Just package your game as a ZIP; it's much simpler.
That being said, the premise is promising, but what I think it lacks more explanation to how exactly the attacks work (what does "bleeding" do for example? Does it take away the enemy's health every turn or does it just do more damage or something?)
Apart from that, I assume that adding more gameplay/enemy types/abilities and improving the presentation are obvious ways to improve your game.