Nice art and sound, I think you had some really cool game mechanic ideas here that I'd love to see fleshed out more and improved upon.
I think I couldn't switch the staff again after I'd done it once and thought the rate of fire a bit slow after that. If the freeze-pillar summoning was quicker, and the pillar could be used for cover from enemies as well as propel you up, and be destroyed by your own bullets quite quickly, I think it would add a nice element to combat strategy. As it is I felt combat felt a little slow.