Adamantine Skeleton (D20 Modern Feat)
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Prerequisite: Regeneration, 17+ Str, 19+ Con
Benefits: +4 Natural AC, Immune to Crippling [physical] effects, 20% chance critical hit counter.
Using the most advanced technology, you have been given an indestructible skeletal frame and can withstand even the most brutal punishment without suffering crippling effects
This feat is a gamble. Without Regeneration, the character would die and there is a chance of death even with Regeneration. In order to successfully take this feat, the player must survive 10 hit die worth of physical damage. In between each damage roll, the player will roll a regeneration hit die. If at the end of the "surgery" the players health total is above 0, the surgery was a success. If the players health total is between -9 and 0, the procedure was a failure but the player survives and loses the feat. If the players health total is -10 or beyond, the player dies.
When in combat, the player is immune to physical crippling effects. If an enemy successfully lands a critical hit, the player may roll a percentage die. If the player rolls between 1-20%, the critical strike is negated and takes normal damage (The effect is as if the critical strike came in contact with an adamantine bone before hitting a critical organ or area).