You emanate an aura that saps the strength of others of your kind and channels their energy into you. Each round that a creature starts its turn in the spell’s area and shares both your creature type and at least one subtype you possess (if any), that creature must succeed at a Fortitude save or take 1d4 points of damage. You gain a number of temporary hit points equal to the amount of damage you deal with this spell (maximum 10 + your caster level). These temporary hit points go away when the spell ends.
As long as you have at least 5 temporary hit points while this spell is in effect, you gain a +1 competence bonus on attack rolls, saving throws, and skill checks. If you have 15 or more temporary hit points, this competence bonus increases to +2.