Steel Skeleton (3.5e Feat)
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Steel Skeleton [Necromantic]
Undead you create have their skeleton structure reinforced by steel
Prerequisite: Able to create undead, Iron Skeleton
Benefit: When you create an undead creature you may choose to add a 10 lbs of steel and an emerald worth at least 50 gp to the material components of the spell. If you do, the undead creature gains 4 hitpoint per Hit Die. A skeleton created with this feat also gains +4 natural armor, gains +2 Attack, and deals +2 damage with its claw attacks. An undead created in this way counts as two Hit Dice higher for the purposes of creating it and controlling it.
Special: This feat may only be applied to undead that have an intact skeleton (skeletons, zombies, ghouls, but not ghosts, for example). You may not apply this feat to an undead in conjunction with any other feat that reinforces its skeleton.