Heh, an enjoyable waste of time!
No, I mean it. This thing WILL distract you from whatever you're doing at the moment. Despite the usual gang of naysayers who try to pull down NG movies for the hell of it, I really did like this. The idea of duplicating what fighting games do - releasing secret fighters and what not when you meet a condition - is pretty clever.
The fighting itself is limited, and doesn't require much strategy, so don't expect to be playing this for days on end. But the real charm of this flash doesn't lie in the technical stuff, but the idea of the more (in?)famous people in the Newgrounds world that have survived the BLAM club to become... well, legends(?).
Anyways, for what this movie worth, it was really something. And yes, I do agree; you NEED to make more of these. It only goes up from here, eh?