The light infantry is the basic infantry unit of both sides in Tiberian Sun.
While modest in performance, they are cheap to train and easy to mass, although quite susceptible to area effect weapons and squishing. GDI infantry is at an advantage, as they have Combat Medics to assist them on the battlefield, whereas the Brotherhood soldiers have to fend for themselves and persevere.
GDI light infantry wear simple combat armour, protecting the torso and groin area combined with kneepads and a combat helmet with an integrated air filtration module, communicator and heads-up display during the Second Tiberium War. The basic design is so efficient that all infantry units are equipped with these suits, with appropriate modifications to suit their battlefield role (e.g. Disc Throwers have backpacks containing the discs).
The Brotherhood equips its soldiers with advanced body armour, protecting their torso, arms and hands as well as legs. The helmet is an advanced model, featuring an integrated communication unit, air filtration systems, infra-red viewing modes as well as faceplate protection, which was absent in GDI armor suits.
They are armed with M16 Mk. II automatic pulse rifles in .22 caliber, developed basing on the M16 and GAU-3 Eliminator rifles used in the First Tiberium War. These rifles are faster firing, more durable, and have an integral multi-function projectile launcher.
GDI infantry can man drop pods and arrive at any location in the entire world within minutes. This ability gives GDI much needed rapid-response ability, and allows it to engage Nod faster than by conventional means. Through this and the ion cannon, GDI hopes to counter Nod guerilla tactics.
After the Firestorm Crisis, Light Infantry formations were eventually succeeded by Nod militia (who, in certain regions, wear Light Infantry armor) and GDI riflemen squads, though the former only arrived as the need rose for large amounts of troops instead of a few soldiers. It is rumored that the remains of Nod's Light Infantrymen, along with the Elite Cadre, have been promoted to the Shadow Team or the Black Hand corps, as they only composed of the "true believers" of the Brotherhood, as the Militants are disillusioned civilians.
The Light Infantry are the most easily massed unit in the game. They require only that the player build a barracks or Hand of Nod, and can be built in vast quantities in relatively little time. They have few abilities of note. They gain veterancy, which increases their firepower. At Elite status, they automatically scatter when engaged. When fired upon, they can go to ground - this decreases their movement speed (crawling) but increases their defense against incoming fire. However, they have less of an effect against vehicles and buildings. They also can't hit airborne or subterranean units. In multiplayer they are often used for scouting, denying scouting, early game rushes and defending from said rushes.