Pretty good!
As with your Halo 'toon, the thought going through my head the whole time was "If only it was a real game...if only..."
Still, it wasn't exactly flawless. The main problem is the choreography (if it can be called that). Your bias towards the rebel side was a bit too obvious. It was a real case of "How much do you want to bet that droid's grenade will bounce back at him", and "I bet you a tenner he'll be killed, even though when the exact same thing happened to a rebel he wasn't" blah blah blah.
Grievous was wasted as well, as was Darth Vader, and the whole thing in general didn't really have an idea of where it was going. It was just "Wait until the guy miraculously pulls out a grenade we've never seen before and then pause again for 2 minutes". If everything they did had a point to it, the Flash would have been more fun to watch.
But still, the idea's good, although Halo Armageddon was much better.
(just please, PLEASE don't make Lord of the Rings World Party or anything. That franchise is getting overused. :) )