Suprisingly good
Well done with this. Some of the animation is a bit rough, I think you're thinking too rigidly if you get me - everything is either facing sideways, backward or forward - there's just no angle anywhere. Your marines firing from higher ground was excellent, and the firebats were great too (great SFX those ones). The ending was brutal, and I mean brutal. In the bad way, it just cuts - just because it's to be continued doesn't mean it can't have a vague kind of closing or something.
It's much better than your earlier efforts, good work! Keep it coming. Your zerg characters are nicely done, I've worked with them myself and they're a real pain to do so I can apprechiate what you've done getting them realistic and not comical looking.