You have a good foundation to build on but you need to work on the perspective and probably the tile size (except this cramped feeling is what you intend). Looks like movement is triggered by "KeyUp" rather then "KeyDown" which is unexpected and acts as a road block in continuous movement. You may want to reconsider this decision.
Besides that, I had fun. I slayed green boxes and healed myself in the blueish boxes.
Any plans for this post-jam?