Warning: Spoilers follow

In the computer game series Command and Conquer, Tiberium is an alien crystal that suddenly appears on the Tiber River in Italy in 1995. It leaches metals out of the soil, leaving it depleted and forms vast beds of crystalline Tiberium. It is suspected that the Scrin, an alien force that was observed by both GDI and Nod, is the culprit who released Tiberium upon the Earth.

The Scrin posessed an artifact, which Nod dubbed the "Tacitus", that can control the growth of Tiberium and its mutagenic effects. Nod also employs Tiberium Gas missiles.

Over time, it is discovered that Tiberium mutates living things and can create some rather disturbing creatures.

In Firestorm, CABAL (under Kane's control) attempts to create new variants of Tiberian life. Nod and GDI form a temporary alliance to stop the mad CABAL and prevent its Cyborgs from taking control.

Varieties

  • Riparius - Color: Green. This is the first form observed. It is spreads rapidly, but has a rather low concentration of leached materials.
  • Vinifera - Color: Blue. This is the more potent and highly explosive variant of Tiberium. It is extremely valuable, but mutates living things much faster as well.
  • Gas - This is a dangerous form of Tiberium which forms toxic clouds. Often observed being emitted by Tiberian Veinhole Monsters.
  • Sea Tiberium - Tiberium that poisons and clogs waterways. The oceans are mostly filled with this form by the time Tiberian Sun takes place.

Tiberian Life Forms (mutants)