Soul Transmutation (3.5e Feat)
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Soul Transmutation [Gate]
Knowing how to utilize the souls of others allows you to utilize your own soul when things grow grim.
Benefit: Make the Alchemy check as if you were using a philosopher's stone, and then subtract from your maximum, venerable, old, and middle age 1 per 5 points used in the check. At the end of your turn, make a Fortitude save with a DC equal to the Alchemy check or fall unconscious.