spell that deals damage to everyone around you equal to you current health and in return brings your health to 1 hp

exploding corpse, but its probalby been mentioned

A spell that lets you steal bodies of the weak and control them to do your dastardly deeds, make them jump off a cliff or set off one of their own traps...
While spell is active your body is left vunerable, and if spell misses you are unconscious for 10 seconds (Basically you take on their point of view)

Maybe a spell that allows you to possess dead bodies?
that would be great for stealth!!!!!!!!!!!!!!!!!!!!!!!

The only magic I would consider to be 'Dark' consists of blinding the enemy, removing/shielding light sources, or absorbing all surrounding light.... bliviongate:

Back in the days of the Call of Ctulhu pen and paper game, they called their equivalent of TES's damage health 'Shriving' : to relieve someone of a burden, the burden of life.

Necro in general

Most of the spells I want are effect based, that also require a different system..

Flense the skin of the target is torn from his body.
Disentergrate, turn the target to ash.
Petrify, turn the target to stone.
Skull mob a whole bunch of skulls fly at the target crushing and bitting him, forcing them to run away.
Nightmare, enter a dream world where you duel with an NPC's subconcious.
allowing you to kill them or posses them in some way without drawing attention in the game world.

Undectable aura, guards and npc's are far less likely to detect your actions.
Note unlike chameleon this does not make you invisible, just less likely for a guard or owner to responed to a minor crime.

Destroy undead, like turn but deals great damage to undead with no chance of spell resistance or reflect.
Ventriloquist, A distraction to make NPC's move / look elsewhere.
Change appearance, disguse yourself as someone else to avoid imprisionment or assassins.
Blur, a chance for attacks to miss the spell caster completely.
Ghost touch, deliver hand to hand or touch spell attacks at range.
Drain level, affects every ability of the target, health, magic, stats, skills all lowered and needs a high dispel or church to cure.
Shadow jump: Move into a shadow and teleport to any other within range, scripted effect cast once, use as many times as you like.