Heal Undead is very useful for necromancers, as it allows for reanimated zombies, conjured Bonemen, conjured Mistmen, and conjured Wrathmen to survive longer in battle. It will synergize well with the Necromage perk, as it increases the magnitude of Heal Undead by 25%. Necromage will also stack with the perk Regeneration and the ability Sailor's Repose, which will yield into an 85% bonus magnitude. This adds up to approximately 140 plus health for any undead targeted.