World with Twin Fates
By ritual sacrifice a necromancer cuts off circulation to his own hand allowing it to decay. In doing so he gains +1 to all implement attack rolls. This increases to +2 at lvl 10 and +2 at lvl 20.
However, instead of harming an undead a necromancer’s implement powers will instead heal them for 1/2 the damage dealt.
Furthermore a dying hand confers awkwardness in social interactions. Provide -2 to Bluff and Intimidate.
A sadistic ritual where a necromancer feels all the pain he inflicts on his hand. In return he can sustain his undead creations much more easily as well as coming closer to his god.