Interesting concept you have here! The arena fights were fun with comboing the different spells, and it was pretty unique allowing the player to ramp up the number of enemies and the difficulty by spending score themselves, with the incentive of making the numbers go up and doing the incremental game exponential growth thing. I will say it was kind of hard to tell what I was supposed to click on with the shop menu at first, but I did figure it out. Might be nice to make it a little more clear what's a button and what's an icon though!
Nice work overall!