Mortimer

Mortimer is the leader of a Bolivian Tiberium cult. This cult controls an area of territory near La Paz, Bolivia, containing several ancient temples. The Firestorm taskforce commander is tasked with retrieving a missing segment of the Tacitus, which according to CABAL can be found in this area. As cult leader, Mortimer seems to command absolute loyalty from his followers, as well as having some kind of peaceful understanding with Tiberium lifeforms such as Tiberian fiends and Tiberian floaters.
Nothing is known about Mortimer's life before the Ghost Stalker encountered him; his age is unknown, but it is possible he grew up near the end of the First Tiberium War, granting him experience with the effects of Tiberium at an early age. It is unknown when his Tiberium Cult was formed or if he is its creator, However he is able to recruit roughly a few dozen members, perhaps more cultists that are unseen. Whether through sheer charisma or brainwashing tactics, Mortimer clearly has powers to make his followers fiercely loyal; when Mortimer is killed, his surviving followers are driven to despair and commit mass suicide. 
There seem to be unexplained forces at work in this region, possibly under the control of Mortimer himself. At one point he appears to "teleport" from one place to another. Elsewhere, as the archaeologist interacts with the ancient temples controlled by the cult, daylight suddenly changes as if hours are elapsing in mere moments (upon entering the "Temple of Time"), and a sudden lightning storm is provoked as the archaeologist enters the Temple of Thunder. It is unknown to what extent these phenomena are under the control of Mortimer himself, or if he has simply tapped into unexplained forces in this region, possibly connected to the ancient temples - or the Tacitus segment.
During the operation to reclaim the second part of the Tacitus, Mortimer was assassinated by the Ghost Stalker, which drove Mortimer's surviving cultists to commit mass suicide in his name. This is believed to be the end of Mortimer's Cult and their influence.
==Trivia==
*When the Scrin appear in Tiberium Wars, they are observed to employ teleportation, and have the ability to create localised ion storms. One could speculate that the unexplained phenomena surrounding Mortimer and the ancient temples could be caused by some related technology, perhaps derived from the Tacitus segment.