VAMPIRIC

self                     Grant energy to self.
bearer                   Grant energy to bearer (if this is an object)
type hit|mana|vitality   Grant energy in the form of hit points,
                         mana, or vitality (hit points is the default).
percent <percent>        Grant the specified % of energy (100 is the default).

You must use parenthesis around your vampiric options if you wish to use more than one.

ex:  (self type hit percent 50)