This is my first review, my ideas for a review might not be to good, but here I go:
Playability:3 You don't actually do anything, the computer does it, but still cool. (Maybe, you could make a twist, where there is a trigger that: if one guy dies, your units attack the other side?)
Balance:4 It was good over all, but one thing i have an idea for is, maybe make the arena look more interesting?
Creativity:4 This was a good idea. In fact, one of my friends had an idea like this, but more of a coliseum like thing, so that there would be people looking on.
Map design:5 You put a lot of detail into the map, and I think it looks really cool.
Story/Instructions:4 Well, there wasn't really a story behind it (like, why are they fighting out in the middle of nowhere?) but the instructions were, like, all that you need. In fact, I didn't even really put a backstory to my first upload.