The game seems unfinished. Goblins moving through walls, the minibosses not really doing anything but being big (the knight didn't even have sound as far as I could tell), finding the hostages has no influence on the player whatsoever. The stats are very unbalanced, I had so much health and potions that I didn't even watch the traps anymore but just went through. Once you find the sword circle skill you already have so much stamina that you can just spam it whenever you hear goblins spawn. And the actual thing the game is supposed to be about and named after, slaying the king, isn't even in the game as you just won when you enter his room (which you know because it says so on the floor, the game just continues).
I like the sprites and the general idea, while nothing original, is good, but the game needs some work.
Then again I often enough ran into the trap of setting way too large scopes for game jam ideas myself, so this is not unfamiliar :D