Fun little game, but with some balance issues ( to say the least :P )
I think the UI was nice, but a bit too simple. Be a bit more directive in what you give the player. First time i thought the interface showed me the controls while actually, it gave me the option to select a wizard ( very nice touch and adds to replayability ).
The gameplay itself was kinda slow and with only having one attack going on, gets quite boring too. Adding a bit more options to limit the other player would be a nice improvement.
As for the wizards, i found that Fire trumped all. One hit, 2-3 dps ( i think? ) Which is insane on the total amount of 10. Dibs on fire!
Besides this feedback, it was just a solid entry and you did a good job in getting this done within the limits :)