Soul for a Soul (3.5e Variant Rule)
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Soul for a Soul
Using this rule means every resurrection attempt must have an equal and alive soul for a sacrificial exchange and failed resurrection attempts kill the caster. All Necromancy is disabled while this is active. Undead is nonexistent while this is active. People are aware of the soul for soul rule of life and either will or won't attempt to break this rule unsuccessfully. Resurrection scrolls and magic items are nonexistent and shrivel to dust upon successful creation.
This rule requires a thanks for the Full-metal Alchemist Anime for this idea.