You can drain the energy of others to enhance your own.

Requirements: Psychometabolism feat

Check: You can drain vital energy from a living creature in your line of sight, dealing nonlethal damage to them. Your Drain Vitality rank sets the damage: 1d6, plus 1d6 per 5 skill ranks. A successful Will saving throw negates the damage. You reduce your own current nonlethal damage by an amount equal to the nonlethal damage you deal using this skill. Once your nonlethal damage is reduced to 0, you do not gain any further points from Drain Vitality, although its targets still suffer the normal nonlethal damage.

Special: You can take 10 on a Drain Vitality check, but you can’t take 20.

Time: Drain Vitality is a standard action.

Strain: 2 (which can be recovered from points gained using this skill).