Item
Emerald
The stone that drinks negative energy, and the necromancer's real budget
A cut emerald attracts negative energy and holds it steady. Set into an undead or partial undead, it increases the animating spell's Dispel DC by 25% (see 3).
Raise Undead consumes one emerald per corpse. At 200 gp each, a hundred skeletons cost 20,000 gp before they rise. Faint Current does not require a gem, but can use one.
Jewellers sell emeralds without question. Buying them by the hundred attracts the council's attention.