Graha Vestige (3.5e Monster)

''There is an alien invisible presence in this room. It is unseen and silent, but it exudes a mental pressure being nearby.''

It is said an alien race of psychic beings had discovered immortality and transcended the chains of mortality into purely mental energy beings which spread across the cosmos. These beings are usually depicted as ancient wise precursors of strange and perfect intellect. However, if these creatures are the same thing as what are known as the graha, then their seemingly utopian end may not have been the end of their story.

Graha vestiges are the remains of a lost alien race which had discarded their bodies long ago. Be it a longing to return to the flesh or the discovery of something horrible on the other side, the graha did not desire to stay in these body-less forms. And yet they had no way to return, as they barely had any presence within the universe as it was. Little more than unattached thoughts, they use their powers to guide mortals to strange alien artifacts and devices, activating eldritch rituals, and other unusual behavior which presumably would help them return to the world in bodily form. Or... something else more sinister.

Graha vestiges don't appear as anything as they are naturally invisible, incorporeal, and odorless. They would be completely undetectable were it not for a faint mental pressure in the room, and their occasional interventions manifesting powers and stealing bodies to puppet them to do their bidding. They are also responsible for a unusual act of conversion into a new species known as the Uplifted. They show up as a vague glowing light under detect psionics.

Graha vestiges "speak" in telepathy and know Abyssal, Celestial, Infernal, and typically five other languages from the local planets they haunt.

Combat
Graha vestige take advantage of the fact most creatures can't hurt them, being body-less and difficult to find. They usually turn enemies against each other or drop summons and other decoys, then flee the scene unless they are out for a specific goal, such as stealing a body.

Immunities : Graha vestiges are immune to blindness, dazzling, deafness, disease, entangling, exhaustion, fatigue, nausea, poison, sickening, paralysis, petrification, and polymorphing.

Naturally Invisible : Graha vestiges have almost no physical presence and are naturally invisible, as if under the effects of greater invisibility. If seen by see invisibility, it appears to be a vague spherical cloud of pale energy. This ability is not subject to the invisibility purge spell. When killed, graha vestiges evaporate and leave no visible body.

Possess :  Graha vestiges can possess creatures with an intelligence score of at least 3. They must make a incorporeal touch attack, which grants the target a DC 17 Will save or become possessed. When possessing a creature they assume control of the body as if using control object to move them around with no concentration, weight limit, and unlimited duration, and the graha vestige may take physical or mental actions as appropriate. The target can resist once a round. A successful save prevents any physical actions that round, while a subsequent second save next round ejects the possessing graha vestige out of their body and ends the possession.

Possession need not be hostile. A willing creature can be possessed and retain control over themselves during their turn, while the graha vestige can puppet their body around and used psionic powers on its turn. These beneficial possessions offer a +2 on any d20 roll once each round from a constant aid another attempt.

While possessing a creature, the graha vestige is effectively unable to be targeted. Attacks directed at it hit its possessed body instead, with the exception of attacks which strike at the mind such as mind thrust which hit the graha vestige directly. If the graha vestige's possessed body falls unconscious, the shock ejects them from the body. It can attempt to re-possess the creature once they become conscious again.

Powers: A graha vestige manifests powers as a 4th-level psion (telepath). They know false sensory input as a 2nd level power for free.

Typical powers known (27 power points, save DC 15 + power level) 1st-deja vu, disable, empty mind, mind thrust, psionic charm; 2nd-aversion, false sensory input, id insinuation, psionic suggestion, read thoughts. The save DC is Intelligence based.