quote taken from PlanetUnreal's description of the Epic Bonus Pack for UT2K3:
Invasion: In this game type, players band together to defend against waves of incoming monsters -- including many of the monsters from the original Unreal. Players cannot respawn if they die during a wave, but as long as one player makes it to the end of a wave alive, everyone respawns for the next wave.
I'm d/l-ing now, was just wondering if it's really as close as it sounds...