This supernatural ability bestows vital energy at a touch, and happens automatically when a melee or ranged attack hits. Each successful energy charge bestows one or more positive levels (the creature's description specifies how many) on living creatures. Unless otherwise specified in the creature's description, a draining creature loses 5 hit points for each positive level it bestows. A creature may not have more positive levels than its Constitution bonus (minimum 1).
An affected creature gains a +1 competence bonus on all skill checks and ability checks, attack rolls, and saving throws, and gains one effective level or Hit Die (whenever level is used in a die roll or calculation) for each positive level. A spellcaster gains one spell slot of the highest level of spells she can cast and (if applicable) one prepared spell of that level. These gains persist until the positive level goes away.
Positive levels remain for 24 hours or until removed with a spell, such as restoration. After 24 hours, the positive level automatically goes away.
Undead react to positive levels the way nonundead react to negative levels. An undead character with negative levels at least equal to its current level is instantly destroyed. After 24 hours, an undead must make a Will save (DC 10 + 1/2 attacker's HD + attacker's Cha modifier). (The DC is provided in the attacker's description.) If the saving throw succeeds, the positive level goes away with no harm to the creature. The afflicted creature makes a separate saving throw for each positive level it has gained. If the save fails, the positive level goes away, but the creature's level (or HD) is also reduced by one.