The Hierarchy act as the highly aggressive brute force faction in Universe at War. Rather than employ a standard base, the Hierarchy instead has the majority of their base functions mounted on a walking chassis. The three largest of these walkers ( Habitat, Assembly, and Science Walker) all feature a unique Hardpoint mechanic that allows them to be customized to suit a player's playstyle preferences or the needs of the moment. The Hierarchy is also the only faction that has repair functions tied to combat units ( Defilers and Saucers for infantry and vehicles respectively), allowing them to perform in-field repairs freely without taking builders away from their own tasks.
Novus is a highly micro-intensive faction that specializes in a mixture of "hit-n-run" and swarm tactics. The faction possesses some of the most nimble units in the game and the ability to quickly transmit them between structures that are connected to the Flow Network, allowing Novus to attack and recall units to defend against counter-attacks extremely quickly. Being a faction of robots, Novus is able to Patch new functions into units at a moment's notice, potentially supporting up to two such patches at a time with both a Command Center and Science Center.
The Masari are an attrition-based "turtle" faction that relies on their superior economy (they do not harvest resources from the map) to eventually wear down the enemy with units and defensive structures. The Masari employ the Dark and Light mode system as their unique tactical dynamic. In Dark mode, all units (and structures with research) gain Dark Matter shielding, an increased rate of fire, increased speed, and slowing on any attacks dealt. In Light mode, the units instead gain increased sight range, a damage over time burning effect for their attacks, and significantly increased damage, though rate of fire is slightly reduced. Furthermore, Masari air units only fly while in Light mode, landing while in Dark mode to instead act as heavy infantry.
Humans Human military forces only appear in the campaigns, though were originally intended to be a fully playable faction in their own right. Many of their units still exist in the game's XML files and can be unlocked for use by existing factions with a bit of editing. Human civilians on the other hand appear frequently on virtually all maps in the game, either as already present bystanders or spawned by civilian structures that suffer damage (either by harvesting or collateral damage).