Assimilate(Expanded Psionics Handbook, p. 76)
Psychometabolism [Auditory, Visual]
Level: Psion 9, Wilder 9,
Casting Time: 1 standard action
Target: One living creature touched
Duration: Instantaneous and 1 hour; see text
Saving Throw: Fortitude half
Spell Resistance: Yes
Your pointing finger turns black as obsidian. A creature touched by you is partially assimilated into your form and takes 20d6 points of damage. Any creature reduced to 0 or fewer hit points by this power is killed, entirely assimilated into your form, leaving behind only a trace of fine dust. An assimilated creature's equipment is unaffected.
A creature that is partially assimilated into your form (that is, a creature that has at least 1 hit point following your use of this power) grants you a number of temporary hit points equal to half the damage you dealt for 1 hour.
A creature that is completely assimilated grants you a number of temporary hit points equal to the damage you dealt and a +4 bonus to each of your ability scores for 1 hour. If the assimilated creature knows psionic powers, you gain knowledge of one of its powers (chosen by the DM) for 1 hour. You gain some semblance of a creature you completely assimilate for 1 hour, granting you a +10 bonus on Disguise checks made to appear as that creature during that time.