The Abh-kamu are a remnant device from the technology of the Onvitaikayan. They are actually protective mechanical suits built by ancient humankind for traversing and working in hazardous environments after the Earth's surface became inhospitable. They were a vital tool in the Gaiaremediation project, which were the efforts made to restore the surface into a livable state for humanity. Their name is an unintended simplification of their original make and model, "Abel Heavy Industries Kamul type-3" which was shortened to "Abbu-Kamu".
They can be controlled from the inside by qualified "pilots", or controlled remotely via a control panel.
Throughout the series, the Abh-kamu have had the appearance of armored humanoid giants. While their original purpose was hazard protection, they have been re-purposed for military use and are often seen wielding swords and shields. Though their appearance during gameplay makes them seem only around twice the size of an average person, the game's artwork suggests they stand over 10 meters tall. Their "armor" is bulky and silver, and they appear to be wearing a helmet with two blue lights that seem to act as eyes underneath. Under the armor can be seen arms and legs with a dark maroon color.
In the original Utawarerumono, the Abh-kama were deployed by Dii against Hakuowlo during their war over Kunnekamun. Afterwards, it seems as though the Tuskur military stored all the Abh-kamu away in Onvitaikayan ruins underground, and chained them to walls for fear of them coming back to life and wreaking havoc. Upon discovering how to control them, Kuon reactivates a group of them and uses them for herself to turn the tides of a losing battle against Woshis' army of Noroi and Rhana-Ahfman.