[@Holy Soldier]

Alright so before I make a dragon related concept I want to try something different with something I've been basically working on for a while but haven't had a lot of roleplays on the site to express it.
NECROMANCY
Warlocks that have the powers over life and death, the cycle and its organic components. Necromancers have the potential to become the grim reapers of the mortal world, spells that could decay living flesh into dust or make an apple grow from a leaf. While necromancers have a potentially indefinite existence it takes a very long time for them to learn different powers
Necromancers, whos' existences represent mastery over the cycle of life and death, can walk in death as they can walk in life. Destroying them or killing them doesn't really do much in the long run as even if they cannot continue their bodies from living into undeath, they can recreate their bodies from other organic material. They do have their limits, exhausting their power can send them into a hundred years or more of a non-existing coma, where they essentially 'stop existing' for a while. If they do not have bodies, their only power at that point is to move as a gaseous, ghost-like and intangible essence invisible to the naked eye and recreate mortal bodies from transmuting other organic matter. The longer they remain without a body the more they are drained of their power, risking them to go into that coma should they keep themselves out of a body.
If they are undead, as in, they are merely controlling a dead body, they are limited to only using necromancy as they cannot technically use other magic in this state, simply due to the fact by all technicality they are 'dead'.
While they have most access to their necromancy and perhaps other magic they may know, keeping them alive hinders their mobility as apposed to floating without a body or the flexibility of controlling a dead one, yet their existence constantly draws them to be alive less they be slowly consumed by the void until their eventual return. 
Necromancers are of the cult of Hecate, a goddess of black magic and, of course, necromancy, and so far it is exclusive to the original necromancer and his children.
-As a side note, necromancers cannot bring people back to life, at least by themselves, as their powers to not extend to the souls of people. Though some necromancers can make new life instead of simple undead creatures, they cannot bring back those that have passed away.-

Added plot for this little pitch.
The character I had in mind was a rebel to the cult he was born into, and helped the government seal his necromancer family beneath some important building or rune. Since then he works as a Syndicate agents using his paranormal powers for the sake of protecting the mortals. He will have a limited use of necromancy aside from being able to reanimate himself, and mostly relying on his knife and revolver in addition to reanimated himself for a rather interesting combat.