It was discovered after Will Zimmerman encountered Gregory in the spirit world during the Big Bertha crisis, and was given clues that helped Helen Magnus to find the items necessary to bring the hologram to work. After they had found a way into Hollow Earth, Magnus and her team soon discovered that the hologram was a representation of the city of Praxis. It was given to the vampire queen in exchange for Nikola Tesla's life. When the queen tried to actavate it, the particle accelerator likely exploded and killed the last of the vampires.