Greater Doppelganger

Stripped of any disguise, a greater doppelganger looks much like its common kin: a lean, hairless biped with tough gray skin. That hide stays just as hard whatever shape it wears, so the creature never has worse than AC 2. Old writings sometimes call these perfected shapechangers mirrorkin, and they move with a speed and grace their lesser cousins cannot match.

Like an ordinary doppelganger, it can take the form of any humanoid from four to eight feet tall, but it goes much further. Full ESP and telepathy let it read exactly what a target wants to see, so it can approach as a trusted friend or a harmless stranger. When the prey relaxes, the creature pulls it into an embrace and drives its claws into the victim's back. Some take the trouble to sculpt their claws so the wounds resemble sword or dagger thrusts, though the damage is unchanged.

Its sharp mind also lets it invent faces and bodies that copy no one at all. In a chase it slips into a crowd and becomes someone new at every corner, changing clothing as easily as features.

Sleep, charm and hold spells have no effect on it, and magic that reads alignment learns nothing. Most psionic probes are fooled as well. Only true seeing or a similar effect reliably exposes one in disguise. It saves as an 18th-level fighter.

Where several doppelgangers live together, a greater one is almost always in charge. Others live alone, or quietly take the place of someone they have consumed. They will make alliances but refuse to take orders from anyone except another of their own kind.

Eating a person's brain lets the creature absorb that mind entirely. From then on it can wear that person's shape with 100% accuracy, along with their memories, skills, alignment and physical, mental and magical abilities. Priestly granted powers and spells above 2nd level do not transfer, since these come from a deity. Even a paladin can be stolen this way, but only the fighting ability survives; healing and other special gifts are lost.

A greater doppelganger can hold up to eight identities. Trying to absorb a ninth or more carries a 50% risk of losing an older identity to make room. It cannot mix them: one person's knowledge is unavailable while it wears another's shape. In its natural form it has only a hazy grip on all of them, such as the languages they knew and general facts. If it must act against the alignment of its current identity, it has to change shape or is thrown back into its true form for 1-10 rounds. Whatever shape it wears, it can use magical items it understands.

Because it can keep a stolen identity for good, a greater doppelganger thinks far beyond the next meal or theft. It works its way into councils, guilds and noble houses without raising suspicion and pursues long, subtle schemes. Births are rare, and the mother must hold a female form for the entire pregnancy or the unborn young dies.