The shopkeeper leads you to a back room, then turns and smiles a horrible grin, reaching out with suddenly harsh and crooked claws…

Invidian (CR 3; XP 800)
CE Medium monstrous humanoid (shapechanger)
Init +0; Senses darkvision 60 ft.; Perception +9
AC 16, touch 11, flat-footed 15
(+1 dodge, +5 natural)
hp 27 (5d10)
Fort +3, Ref +4, Will +5
Speed 30 ft.
Melee 2 claws +6 (1d4+1 plus grab)
Special Attacks steal visage (grab)
Str 12, Dex 11, Con 11, Int 8, Wis 12, Cha 14
Base Atk +5; CMB +6 (+10 grapple); CMD 17
Feats Deceitful, Dodge, Great Fortitude
Skills Bluff +17, Disguise +9, Perception +9; Racial Modifiers +8 Bluff
SQ change shape (alter self; any Small or Medium humanoid whose visage has been stolen)
Environment urban
Organization solitary
Treasure standard
Steal Visage (Su) If the invidian begins its turn with an opponent grappled, it can attempt a new combat maneuver check. If it succeeds, the opponent must make a Fortitude save (DC 14) or have its face removed. The victim is left blinded, deaf and mute. The victim could also die of starvation if the face is not restored. The invidian may discard the stolen face or apply it to its own face as a standard action. While wearing the stolen face the invidian gains the ability to speak any languages of the opponent as well as its speaking voice and mannerisms. If the opponent dies while the visage is stolen, the masks persists. A stolen visage can be restored to an opponent by a invidian or by powerful healing like a regenerate spell.

The laws of piety regard the sin of envy to be lesser, a sin of the flesh. Those persons that are consumed with envy are monsters in whatever flesh they hold, but sometimes, in the presence of dire and ancient magic, ordinary humanoids are transformed into foul monsters with specific and horrific powers. Such are the invidians. An invidian constantly strives to get “better” faces and identities, though likely the satisfaction of one of these evil things has never been reached.

Invidians have no ‘natural’ form, as the race of dopplegangers do; as they acquire faces from victims, their form becomes that of the victim. A victim of their steal visage attack becomes a horror themselves, and there have been several instances of struggling victims being slain in an invidian’s wake. They become eyeless, earless, mouthless freaks, with only a pair of nostrils with which to breathe. The invidian possessing their face must be forced to return it to the victim, before he or she starves to death.

On Porphyra
Invidians on Porphyra are called wajari, created by a cabal of renegade elementalists that consorted with the newly discovered race of demons. Most also have at least one type of element resistance 3, usually fire.