-Dutch, on the phone
Randolph Dutch is, probably, the main antagonist in Survival Crisis Z. A tall man that seems responsible for almost all paranormal events and entities (and probably the zombie virus)
He lived during the 18th Century, he was, as Professor Danchade says, a lunatic and a prominent gnostic. He formed a secret society in what are the sewers now.
His belief made him kill people in order to send them to the spiritual world and release their souls, since they weren't happy in the material world. Among his victims, it was a woman named Juliet (he had feelings for her but was unable to tell her or she didn't want him)
When he died, he found himself in Hell for all the sins he commited, but he was still obsessed to get the spirit world, the only obstacle was the material world. He then started esnalving souls of women (banshees) and children (undead/ghost children) and at some point he had small control over the material world, transforming it into the Hell Dimention.
He also started to join members to his "cult" as he seek for dead people at the brink of death (like Trevor) or insanity (like Amanda) and offered them a second chance (similar to a deal with the devil). Also, those who tried to stop him, felt victim of his power and became part of his army. He appears as a final boss in the mission "A Dutch for the Road"