Heighten Undead (3.5e Feat)
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 Heighten Undead [Necromantic]
You are able to make undead that are more resistant to turning
Prerequisite: Able to create undead
Benefit: When you create an undead creature you may choose to add an onyx gemstone worth at least 25 gp to the material components of the spell. If you do, the undead creature gains a +2 turn resistance. An undead created in this way counts as one Hit Die higher for the purposes of creating it and controlling it. You can only raise an undead creature's effective Hit Dice to one half your caster level through Necromantic feats.
Special: You may gain this feat multiple times, each time it allows you to apply it again on an undead creature (requiring an extra gemstone and increasing the effective Hit Dice value).