WalkerMK.IV

Global Defense Initiative

GDI's faction symbol

The Global Defense Initiative's internal structure and organization is quite similar to a supranational and large-scale integration of all of the world's major modern day conventional armies into a single globalized military force.
GDI is capable of instantly deploying vast quantities of well-trained
and well-equipped soldiers backed by powerful ground, air and naval
assets to any point on the globe, and this in ways that are
considerably more organized, advanced, as well as on a much greater
scale than any conventional real-life military force of today possibly
could. Global Defense Initiative troops utilize both superior armor and firepower, making them typically much more powerful than Nod
forces in direct open confrontations, but also more cumbersome and less
flexible. The Brotherhood is notoriously adept at exploiting these
weaknesses through its combination of futuristic guerrilla warfare with uniquely advanced Tiberium-based technologies.
By the year 2047 GDI's forces have been restructured to allow for
decentralized operations in multiple theatres of war, through the
establishment of forward-operating bases in all types of terrain,
and the deployment of proven, specialized and cost-effective ground and
air forces supported by the most advanced network of orbital artillery
satellites in history. In-game, their units are unit-for-unit more
powerful than those of Nod and the Scrin. Their superweapon is the quintessential ion cannon,
an orbital weapon that has appeared in every Tiberium title to date;
previously capable of destroying only a single building at a time, the
ion cannon can now devastate a large area, through 8 small ion beams
forming up into the center and ionising the air before the larger, more
destructive main blast.

Brotherhood of Nod

Nod's faction symbol

The Brotherhood of Nod is a mysterious and highly militant Abrahamic society of allegedly ancient origins, which in modern times began showing the combined characteristics of a vast religious movement, a multinational corporation and a decentralized nation-state, while being none of the three in itself. The globalized brotherhood is led by a mysterious man who is known only as Kane, and its influence in the world at the advent of the events in which Command & Conquer 3: Tiberium Wars takes place reached nothing short of the status of an unconventional superpower. The Brotherhood of Nod represents a flexible, elusive and worldwide cultic army which thrives on the sophisticated synergy
between low-tech guerrilla warfare and highly-trained forces that are
equipped with state-of-the-art communications gear and the most
advanced weapon systems available, which have been derived from the
Brotherhood's uniquely adept understanding of Tiberium-based military
technologies.
Nod tactics are highly radical and appear more cruel than GDI's, often
showing little to no regard for human life, and their religious
fascination with Tiberium also leads them to use the dangerous and
toxic substance offensively whenever possible. Nod forces typically are
weaker than GDI's or the Scrin in a head-on engagement, yet their use
of stealth and advanced hit-and-run tactics to their advantage to control the pacing of the battle, as well as sabotage an opponent's momentum. Like in the original C&C game, their in-game superweapon is a nuclear missile, which replaces the cluster and chemical missiles deployed during Command & Conquer: Tiberian Sun.

Scrin

The Scrin's faction symbol

The third faction featured in Tiberium Wars is an extraterrestrial force known only as the Scrin, who have come to harvest all of the Earth's Tiberium deposits.
They aren't referred to by name, though a reference of the name exist
in GDI intelligence files: "...the translator returned four words:
brother, ascended, enemy and Scrin. This casts some confusion over the
identity of the invaders, whether they are the Scrin themselves or a
distant relative..."; they are only called by GDI as "invaders" and
"Aliens" and by Nod as "Visitors". They have remained dormant along the
edge of our Solar System for millennia,
until awakened by the massive detonation of liquid Tiberium beneath the
Brotherhood of Nod's "Temple Prime"; it is revealed that GDI knew about
their existence from the Tacitus, an alien databank captured from Kane
at the end of Tiberian Sun; this resulted in the upgraded Ion Cannons,
that can fire on incoming space-born targets with a single,
concentrated beam. Upon approaching Earth, they are surprised to
encounter a heavily militarized native population (according to the
Scrin campaign introduction movie, "Level IV population on 50% of
planetary surface" and "Level V population on 20% of planetary
surface") still coping with Tiberium's spread, and swiftly proceed to
launch an assault on Earth's cities, wreaking havoc on GDI and Nod
alike. This is done mainly for intimidation purposes because the real
objective of the Scrin is to construct large "Tower" structures all
across the planet. Scrin units and structures show a distinctly bio-mechanical and insect-like appearance, and possess several economic and military advantages related directly to Tiberium,
including the ability to promote the growth of the substance, store it
in infinite amounts, and to use it to enhance the performance of their
units and weaponry in a multitude of ways. Scrin forces possess a
powerful aerial fleet,
capable of constructing fast "Stormrider" fighters, hovering
"Devastator" warships and the versatile "Planetary Assault Carriers",
which are capable of generating localized ion storms. The faction also
features the ability to create wormholes
and to instantly teleport units around the battlefield through various
means. The Scrin are additionally able to deploy a large aerial unit
known as the "Mothership", which features a massively powerful Catalyst
Cannon that can devastate all structures in a large radius beneath it
by initiating a chain reaction upon them. However, the "Mothership" is
extremely slow and open to attack. Their in-game superweapon is the
"rift generator", which creates a rip in space-time in the targeted area, drawing everything near to it into deep space.
According to GDI intelligence on the Rift Generator, "it makes the
science behind our Ion Cannons look downright primitive" and "its
destruction potential is on par with GDI Ion Cannons and Nod nuclear
missiles."