Setting Tiberian Sun involves two factions - the Global Defense Initiative (GDI), and the Brotherhood of Nod - and an alien substance called "Tiberium", and occurs after the events of
Command & Conquer. Tiberium has become a serious problem for the world since its arrival in the 1990s, not only in causing a conflict between GDI and Nod over control of the valuable crystals it creates from leeching precious metals from the soil - leading to the
First Tiberium War - but also allowing the substance to slowly spread and terraform the planet's ecology and landscape, including causing mutations in humans, the formation of new alien lifeforms, and the development of new weather patterns called Ion Storms. By the 21st century, GDI is focused on researching the means to combat Tiberium's spread, making use of an orbital space station called the
Philadelphia to command its forces, while Nod has splintered following the presumed death of its leader
Kane, with both factions working to develop new technology to provide each with equal strength in their armies, including armoured walkers, cyborgs, advanced defensive measures, and armoured infantry. The campaigns of
Tiberian Sun focus on a new global conflict erupting in 2030, when Kane returns and re-energises Nod, forcing GDI to combat their efforts, and resulting in the Second Tiberium War. GDI's campaign focuses on the efforts of a commander who must combat the sudden surge of attacks, working alongside a faction of mutants known as "The Forgotten", in order to thwart Kane's latest plans with Tiberium. Nod's campaign focuses on the efforts of an officer who escapes execution by a de facto leader, controlled by GDI, and works to reunite Nod in order to complete Kane's plans.
GDI Campaign (Evolutionary Response) GDI commander
Michael McNeil is recalled from a training exercise to assist in combating Nod, after being informed by his superior, General James Solomon (player character in the first game), that Kane has returned. McNeil is assigned with initially pushing out Nod forces from GDI territories in North America, led by Nod general and drug lord Vega, before Solomon assigns him to assist a recon team in securing a ship of alien origin that the Brotherhood have taken an interest in. Although the ship is secured, GDI finds it cleaned out by Vega and proceed to track him down, coming across a mutant named Umagon who requests their help in rescuing Tratos, the leader of the Forgotten, who can help explain what Vega stole. Discovering that the ship contained an alien database called the Tacitus that Kane sought, McNeil pursues Vega to his base in Central America. Cornered and learning that Kane has no further use for him, Vega takes a fatal drug overdose before his base is nuked, informing McNeil before he dies that the Tacitus is already being shipped to Nod's base in North Africa. Learning that Nod is targeting GDI's research in Northern Europe, which focused on creating sonic crystals that can help combat Tiberium's spread, McNeil is assigned to reclaim an important GDI base in the region, before pursuing the stolen crystals. GDI soon learns that Kane has developed chemical missiles that can accelerate the spread of Tiberium across the continent, forcing McNeil to combat the imminent threat it poses along with eliminating a factory developing a new aircraft for the Brotherhood. Eventually, GDI moves towards Egypt to combat Nod at their main base in Cairo, only to learn that Kane's ultimate plan is to launch an ICBM missile containing a warhead of pure, concentrated Tiberium, that can transform the entire planet. Against the advice of Solomon, McNeil launches a direct assault on Kane's base, ultimately destroying the missile and killing Kane, ending the conflict once again, and securing the Tacitus for GDI's research team to analyze.
Nod Campaign (Deus ex Kane) Anton Slavik, an officer of Nod's elite unit called "The Black Hand", is arrested by the Brotherhood's new leader Hassan, who is a GDI spy. Before he can be executed, Slavik is rescued by a member of his crew, posing as a Nod journalist, and begins working to reunite Nod in Northern Africa, with the assistance of the Brotherhood's AI CABAL. Shortly after capturing Hassan and ending the internal conflict within the Brotherhood, Slavik reveals him to be a GDI puppet. Before Hassan is executed, Kane announces his return, fully reuniting Nod's splinter factions. Pleased with Slavik's work, Kane assigns him to disrupt a GDI excavation at Nod's former temple in Sarajevo, in order to prevent them locating an alien database and a special project housing it. However, Slavik finds the project missing, having been taken by Vega. Forced to North America to retrieve it, Slavik and his crew recover the missing project and the database (the Tacitus), but are tricked by GDI into attacking a research facility, leading to them being captured. Imprisoned in a base in Northern Europe, Slavik receives a message from CABAL that a Nod strike force has arrived to rescue him, and executes a plan that leads to his escape. Learning from Kane that he has completed a new missile that will give Nod an ultimate victory and shape the future of the planet, Slavik implements operations to disrupt GDI's research into a new advanced battle walker, and captures a member of a highly advanced GDI base in order to infiltrate it. With Kane's plan nearing completion, Slavik attacks the base, captures it, and uses anti-satellite weapons to destroy the
Philadelphia. Kane then launches his missile, achieving ascension and vanishing, while transforming the Earth into a Tiberiumized planet that he had envisioned as humanity's evolutionary future. ==Development==