Hi!
The thing with the shop is to give some feeling of progress, I was thinking of adding player levels and perhaps requirement of player level to weapons but I have to think it.
The animations and the AI are at the top of my To Do list for future patches for the game.
Behind the last door should have been the king, like I said to another comment, but your comment gave me the idea to add some scene when you break the door to present the boss to the player. Thanks!
The ting about the HP bar is that I have to rearrange all the layers for all the sprites because right now is a mess.
Thank you for the comment and the feedback!