Murakumo Millenium is a corporation first seen in the original Armored Core.
This large corporation is mainly involved in industrial manufacturing. Their reputation is particularly strong in AC-related products, and their technical prowess is said to exceed even that of Chrome. They are also one of the few corporations who have made clear their opposition to Chrome's plans for monopolistic rule. For this reason, military confrontations frequently occur in the vicinity of Isaac City.
They are also responsible for the production of Human PLUS, which is revealed to be technology from before the Great Destruction. In the Chrome Path, Murakumo becomes the main antagonist, with their ultimate plan being to activate Justice. No matter what path the player takes, Murakumo eventually loses power and breaks up.
Before its breakup, it is revealed later that Murakumo had begun a terraforming project on Mars. After its abandonment, Zio Matrix discovered the project and completed it, setting the events for Armored Core 2.