Adds new maps, 8 player support, deathmatch, single-player, Antlion Guard into Alien Swarm without changing its concept.
Requires version 1.13 installed. Extract to <path to steam>\SteamApps\sourcemods. Restart Steam. This update adds Antlion Guard from HL2 which spawns in Onslaught mode. Some fixes to Extermination maps 1 and 2.