Infection

This set of 7 maps should take around 45 to 60 minutes to complete on Ultra-Violence, provided you don't die too often. It is designed to be played in order, but pistol starts are possible with some added difficulty.

UAC Research Base Delta has unexpectedly gone dark. Delta base, situated in an undisclosed location in the northern United States, is tasked with experimenting on salvaged remnants of the demon army that invaded Mars. Your job is to find out what the hell happened and at your own discretion, take care of whatever evil is taking place there now.