Entertaining
Really addicting, great skill tree, etc, etc. A couple of things, though. First, I saw someone mention polish--I don't know if he was talking about graphics or what, but if he was, then I'd have to disagree. Granted, it's not the most stunning game out there, but that doesn't change the fact that it's fun and it looks decent. I did, however, run into a "polish" problem of my own: during some levels, I couldn't use the fireball ability or the "allegiance" ball (don't remember what it's called) ability. I could use lighting just fine, but I hadn't maxed their cooldown, so I ended up getting a bit screwed. Whenever it froze up, the attack animation appeared in the top left corner of the screen. I was playing in pop-up mode, so that might make a difference, but I thought you should know.
Other than that, like I said, you have a really addictive, fun game here. Sure, it's not exactly artistically brilliant, but it's a ton of fun to play and definitely looks good.