You wrap a creature into a cocoon like construction and over the next 2 days the creature is considered unconscious any damage done to the cocoon will lead to a failed death saving throw for the creature. Once the creature emerges from the cocoon they will be able to either re-roll there ability scores or choice different options for point buy, and change there race to any race you have seen losing the old racial features and gaining the ones of the new race. Also allows you to reduce there physical age by up to 10 years (200 years for elves and no less then age 5 for any race). if the spell is stopped after 2 hours or more the creature inside dies.