The RoG (Replacement of God)

The concept of God in the three universes is a bit different. It's not one being, but rather multiple people over thousands of years, inheriting the originals powers. The original, a rogue high-level mage, decided to travel to the gateway universe and call himself God. Religion quickly formed around him as he demonstrated his power.
Before he died, he pieced together a massive spell that would pass on his memories and power to the next gateway User that was born (a rare occurrence to begin with). As each replacement dies, they pass on their memories and power to the next User, with each User becoming more and more powerful. At some point during the years, an organization emerged that decided to weave a spell that would corrupt the Replacements and align their interests with the organization's

Here is a list of the powers each RoG provided to the lineage. The RoG didn’t obtain immortality until iterations 3 and 4.
Original Mage: All base mage abilities, plus water, earth, and wind control
Iteration 1: Teleportation (of themselves and others)
Iteration 2: Ability to bend perception of others
Iteration 3: Age manipulation of self
Iteration 4: Extreme durability, fast healing
Iteration 5: Alchemy
Iteration 6: Ability to create and freely use pocket universes. Includes the ability to travel between universes with no cooldown or consequences
Iteration 7: Minor psychic abilities
Iteration 8: Magic detection and ability to suppress their own magic
Iteration 9: Assimilation. Any knowledge is permanently remembered and usable, unless deliberately forgotten
Iteration 10: Shadow manipulation. Includes shadow travel, usage of shadows as weapons, etc
Iteration 11: Vision: heat, night, etc
Iteration 12: Raze. Manifestation of sheer power. The RoG can utilize his or her power in nearly any way desired, aside from directly modifying natural laws or time.
Iteration 13 (Martin “Gray” Price): Full control over life and death

Martin "Gray" Price

Gray is a self-proclaimed pacifist, usually appearing as a kindly middle-aged man, despite being around 25 years old. He tries not to get involved, succeeding quite a bit more than Jason. Jason and Gray are best friends.