Armored Core

In a distant future, the Great Destruction — a catastrophic war — wiped out the vast majority of humanity. Survivors spent fifty years living underground, during which corporations consolidated power and came to rule what remained of civilization. Chrome and Murakumo Millennium are the two largest, and their conflict for supremacy never stops. Operating independently of both corporations are the Ravens: mercenary pilots who take contracts from whoever pays. You are one of them, and your vehicle is an Armored Core — a giant mecha built for the kind of work the corporations need done but do not want attached to their names.