I thought of another version of Nagash, please have a look
Nagash
M6 WS4 BS3 S3 T2 W5 I6 A2 Ld10
Equipment: Hand Weapon
Magic: Nagash is a Lvl4 Wizard, he will always use Necromancy
Special Rules: Possession, Ethereal, Master Necromancer, Cause Terror, Glide (Fly, 15").
Possesion:
As you may have noticed, Nagash in itself is extremely weak. This forces him to work through vassals, possessing and using their body until it is completely wrecked. Then he goes off to possess another body.
During the movement phase, Nagash may opt to "join" a character or unit champion (friendly or enemy). The Nagash model is placed next to the character/unit champion. If Nagash has joined a model, Nagash cannot be targetted or seen in any way, the model counts as if it wasn't there. Nagash may start the game in a friendly character or unit champion if he chooses to do so.
Any character possessed by Nagash keeps his profile, but has the Magic Levels and Lore of Nagash. note that weither the posseseed is friendly or enemy, the model is always under the
VC player's control.
Any model possessed must pass a Leadership test on a 3D6 every Magic Phase or lose a Wound, due to the unholy magics flowing through his body. If the model passes the Leadership test, however, Nagash himself loses a Wound. Should the possessed model be slain, Nagash may move out of the model and look for a model to possess within 6". If no suitable model is found, Nagash is placed within 6" of his former body by the Vampire Counts player.
Master Necromancer:
Nagash always knows all 6 spells from the Lore of Necromancy. He may opt to cast the Invocation of Nehek at 15+, allowing him to raise 4D6 Skeletons, 4D6+4 Zombies or heal 4 Wounds on any multiwound model (but not himself). Note that Nagash may not cast spells when he doesn't possess a model.
EDIT: Typo fixed