Imma need more info on this
Originally, he was a sweet old undertaker in the old west who made extra money as an inventor on the side. He got, tired of just burying the dead and wanted to figure out where their souls went and so he built himself a sort of door maker.
The device let him crossover but instead of heaven. He entered something else, another universe not quite hell or heaven and when he returned he was hard, cruel and insane.
Over the following century he seemed to develop his technical skills Eben more and subjugated a dimension with hyper gravity where a bunch of malevolent Dwarves worshipped him as a God. He eventually began building his drones..
He began to add to his armies, lobotomizing corpses at first extracting their brains and crushing the corpses down to midget form and using their brains as cpus for his drones.
Dude graduated from that to devouring small towns, moving all across rural America falling upon the decay of our manufacturing capscoty and the dying small towns that created until. Wiping them out and converting them into raw material for his drone armada.
He seems to want to conquer every dimension in the phantasmverse and whenever you kill him, he returns by transferring his essence to another version of himself.
Jebidiah Morningside/ The Tallman is basically some creepy world conquering, Dwarf making. Drone spamming Immortal dude and one of the more unique characters in horror.
It helps Scrimm had an amazing screen presence.
@Es_ can you elaborate better than I can.