United Operations Forces
The United Operations Forces is the name given to the military of the United Human Federation. It is comprised of two departments; the United Operations Army and the United Operations Navy. Each department has millions of active duty personnel directed by UOF command.
United Operations Army
The UOA's duty is to wage surface warfare. They are the largest of the two departments of the UOF, partially due to humanity being on the defensive and being forced back to their cities. Due to the resilience of the Machina, infantry have had to move from select fire rifles towards 20mm coilgun weapons for their ability to reliably harm a Category 3 Machina. These are essentially the same gun system as the basic assault-rifle-style 20mm coilgun operated by REPAIR Agents, but in order for even the enhanced humans of the post-WWIII era to operate these weapons, the weapons tend to be either heavy long rifles or heavy machine guns operated by crews. Most human soldiers also get issued with personal select-fire rifles in the .50 range, often utilizing magnetic acceleration in their operation. These weapons have the ability to deal with Machinium-based creatures such as Larvae and their derivatives, and may occasionally cause some rather minor damage to a regular Machina.
While regular infantry operate cumbersome personal and crew-served weaponry, a great deal of their staying power is derived from vehicles carrying 50mm and 100mm anti-Machina railguns, emplaced versions of the aforementioned anti-Machina railguns, and conventional artillery. The 50mm anti-Machina railgun is the same weapon as fielded by a few REPAIR Agents, and can reliably wound a Queen-class Machina, while the 100mm AFV main guns are able to destroy even Queen-class Machina in short order. Conventional artillery beginning with 155mm howitzers of the style pre-dating WWIII are enough to cause harm to Category 3 Machina within several meters of the explosion epicenter.
In response, the Machina attempt to out-maneuver and bleed-dry the much more static human forces, utilizing their inhuman speed, endurance, and agility to pick apart defenses.
As of the Jupiter system campaigns, there has been a great deal of development in the field of exo-suits and small mecha to better carry around coilguns and counter the highly-mobile and resilient Machina. Other elements of the UOA include infantry fighting vehicles with the ability to carry infantry and main battle tanks, each armed with railguns. A great emphasis is also placed on the use of artillery in both direct and indirect fire roles, to make the Machina more hesitant to attack by disrupting their movements and planning.
The UON performs both atmospheric and exoatmospheric combat. Their vessels include fighters and gunships for operations in-atmosphere and in support of larger craft, as well as various destroyers, cruisers, battleships, and carriers to engage Machina fleets. Included in the department of the United Operations Navy are marines, who use a variety of fast space-to-surface transports. It is also the duty of the UON to transport personnel and materiel of the UOA, who may also engage in 'amphibious' operations in a similar manner.
As with the UOA and their liberal use of vehicles and artillery, the UON manages to keep the bulk of the Machina at bay through the use of overwhelming firepower. In fact, space combat is where humanity arguably has the advantage, as the human warships have no issues with shelling their Machina counterparts who must avoid causing deaths from ship-to-ship combat so they can board and corrupt the crew. Machina must instead launch their attacks from afar and if they are unable to seize a given ship, they must weaken their quarry for a larger assault to come. Such brute force can be circumvented, but it causes the Machina to be cautious in general, buying humanity time.
Navy ships tend to have large main battery weapons, many auxiliary weapons, strong armour, sections which can be discarded to isolate the rest of the ship from corruption, and artificial gravity able to compensate for changes in velocity. Many ships do their best to perform 'silent running' as while the Navy outnumbers and out-guns the Machina, Machina have incomparable speed and maneuverability and could launch effective surprise strikes if the humans alert them to their presence.
