Disorder Units are a class of weapons that are seen throughout Mars in Armored Core 2. There are numerous models, with the most common model being a quad-leg model (although several airborne and bipedal models exist as well). During the terraformation process on Mars, Zio Matrix discovers the Disorder Units and witnesses them wreak havoc on several Martian facilities before finally coming to restrain them. After restraining the deadly units, Zio takes possession of the deactivated Disorders and begins a series of tests and studies in order to reverse engineer, or otherwise manipulate them in the company's favor. Leos Klein eventually learns how control these units and activates all Disorders on Mars (inlcuding the ones under Zio Matrix's possesion), which end up decimating Mars's three largest corporations. With Leos Klein's death, it is assumed that all (or most) Disorder Units immediately became deactivated as well. Some Disorder Units appear once more (albeit briefly) in Armored Core 2: Another Age.
Ameise - Though the quad-legged "Ameise" model is the most common model of the Disorder Units, its destructive output is somewhat mediocre as an individual unit. However, despite the lackluster damage output, this model often appears in great numbers, ultimately making it quite dangerous overall. There are also variations in size among this type of Disorder Unit, but the damage output among these variations is still constant despite this being the case.
Biene - Biene is a red, alternate version of the Ameise with a much more noteworthy damage output. It appears much later on in the game than the Ameise model, and also varies in size like its lesser counterpart while also maintaining a constant damage output across these variations.
Zikade - A slow moving, hovering model; Zikade appears only in small numbers in a few missions. It has a more impressive damage output in comparison to Ameise and Biene.
Sauturelle - This model appears in a Zio Matrix transport, thus implying that it was either captured or reverse engineered. Sauturelle is very agile with many embedded laser armaments.
Predicator- A very powerful Disorder Unit featured as a boss in Armored Core 2, Predicator sports twin energy blades that are equal, if not slightly more powerful, to the MOONLIGHT energy blade seen in other Armored Core installments. This model is specifically designed for close-ranged combat.
Luciole - Luciole is also featured as a boss in Armored Core 2. It features high durability and also contains hard-hitting cannons, as well as homing missiles.
Marienkaefer - Arguably the largest Disorder Unit known, Marienkaefer sports incredibly high offensive and defensive capabilities. It is a multirole Disorder Unit, able to attack at longer ranges with its mounted plasma cannons, and closer ranges with its mounted machine guns. Marienkaefer, because of its damage output and durability, was considered to be Zio Matrix's trump card.
Scarabaeus - A massive, hovering Disorder Unit; the Scarabaeus is the first phase of the Martian Superweapon. It is outfitted with many missile sites, as well as machine guns near its core. It is piloted by Leos Klein.
Filial - A humanoid, very agile Disorder Unit; Filial is the second phase of the Martian Superweapon. It is outfitted with many plasma cannons, a high-powered energy blade, and also makes use of unmanned aerial pods (which look very similar to orbit units from the later Armored Core installments). It is also piloted by Leos Klein.
- Bio-Sensors must be installed in order to lock on to a Disorder unit. This suggests that they may be organic in design.