So I did figure something out let me know if this makes sense

-Rising population on Earth increases amount of Necromancers and undeath anomalies, the nature of souls and soul energy travelling between the dead realms and the living creates reality fluxes that release a special type of Flux Energy
-The Others thrive in large quantities of Flux Energy, and the nature of the increase in Flux Energy caused by the Necromancers draw the Others to our reality
-The Alien Race has been within our solar system for a long time, the population of Earth is resulting of an experiment conducted by them, the threat of the Others draws them to Earth where they plan to drive them off to prevent them from becoming a confound to their data
-The Demons thrive off the chaos of the previous three factions so they jump realms into ours, the more powerful having their own forms and the less powerful possess compatible bodies of the other 3 factions + factionless humans, their main goal is to use the chaos to come out on top and spread influence among three different races at once
-The Necromancers see the demonic possessions as defilement to nature and wish to purify them from the realms, and also see the presence of the Others as an abomination to our reality

Does that give enough motive to each faction for a roleplay do you think?


Also someone mentioned "but where are the humans?"

A) The roleplayers will be playing the humans (And allowed a second non-human character)
B) Each faction will offer a different set of abilities and resources for the humans that wish to join them. The reasons humans are invited to the faction of Others is yet to be determined.
C) Factionless humans will be available but will lack abilities contained in the factions without some form of stealing resources, and will have to somehow come up with their own assets to survive
D) Necromancers are all human, there will be some special humans in this group due to it's nature, some of those being a form of vampire, lich, or etc. 



As for general abilities to be expanded on in each faction:
1) Aliens will offer Psiionic abilities to the humans of their faction, along with extremely high tech. Some of this tech will exist in other factions in smaller amounts because thievery is a thing.
2) Others will offer odd abilities and mutations, things similar to extra eyes and energy based abilities
3) Demons will offer a form of magic independent to Necromancy at the cost of requiring possession, this magic will focus more on fire and manipulative curses and those that use it will be understood as practicioners of witchcraft
4) Necromancy offers the largest sum of possibilities. Necromancy can take the form of Vampirism, Lichdom, the summoning of the dead, the reanimation of dead bodies, and certain decay-based abilities. Necromantic magic will be more of a physical magic with direct effects on the world around them rather than creating something new.


Things I still need to figure out:
1) The anatomy of Others, Aliens, and Demons
	I do know basics though
		A) Aliens will be mostly human in appearance but will have some form of exaggerated features and 	
		extra external organs
		B) Others will be characterized by tentacles and eyes
		C) Demons will be characterized by horns, cloven feet, and skin tinted red or black
2) The culture and history of the 4 factions
3) How to bring the players together consistently enough that it's a successful roleplay
4) The nature of necromantic curses and the like that create Vampirism, Lichdom, and other similar afflictions/transcendence