As the Endless Wars continued between the Imperium and the Soulless, it became apparent that conventional ground forces and manned combat mecha would not be enough. During the siege of Tycho Gryphanne Defiance Industries modified work mecha to carry combat munitions onto the battlefield. Following this make-shift response, GDI contracted with the RMMC to get plans on how to build their combat mechs. The resultant combination of human know-how and Imperium technology created the Autonomous Combat Support Mecha. Armed with twin A/M pulsars, a gattling laser, and a missile pod, the ACSM is the infantryman's best friend.