Doppelganger, Greater (CR 12)

Medium Monstrous Humanoid (Shapechanger)
Alignment: Usually neutral evil
Initiative: +3 (Dex); Senses: darkvision 60 ft., Listen +15, and Spot +15

AC: 17 (+3 Dex, +4 natural), touch 13, flat-footed 14
Hit Dice: 9d8+9 (49 hp)
Fort +7, Ref +4, Will +11
Speed: 30 ft.
Space: 5 ft./5 ft.
Base Attack +9; Grapple +10
Attack: 2 slams +10 melee; or rapier +10/+5 melee
Full Attack: 2 slams +10 melee; or rapier +10/+5 melee
Damage: Slam 1d6+1; or rapier 1d6+1
Special Attacks/Actions: Detect thoughts, polymorph, rend
Abilities: Str 12, Dex 17, Con 12, Int 17, Wis 17, Cha 13
Special Qualities: Alter self, consume identity, immunities, magic item use
Feats: Alertness; Blind-fight; Dodge; Combat Expertise
Skills: Bluff +15, Diplomacy +5, Disguise +15, Intimidate +3, Listen +15, Search +13, Sense Motive +13, and Spot +15
Advancement: By character class
Climate/Terrain: Any land and underground
Organization: Solitary
Treasure/Possessions: Double standard

Source: Monster Compendium: Monsters of Faerûn

Detect Thoughts (Su): A greater doppelganger can continuously detect thoughts as the spell cast by an 18th-level sorcerer (save DC 15). It can suppress or resume this ability as a free action.

Polymorph Rend (Sp): Greater doppelgangers are masters of form. As a spell-like ability, a greater doppelganger can make a touch attack against a being that is presently enchanted by a polymorph self spell, a shapechange spell, or a polymorph other spell cast by someone other than the greater doppelganger itself. This touch attack inflicts 6d6 points of damage on the polymorphed creature.

Alter Self (Su): A greater doppelganger can assume the shape of any Small or Medium-size humanoid. This works like alter self as cast by an 18th-level sorcerer, but the doppelganger can remain in the chosen form indefinitely. It can assume a new form or return to its own as a standard action.

Consume Identity (Su): A greater doppelganger who eats the brain of a Medium-size or smaller humanoid victim absorbs the mind, memories, and personality of that victim. After consuming a victim's identity, the greater doppelganger can assume the victim's form with 100% accuracy and possess the victim's memories, abilities, and alignment. The only exceptions are cleric spells of 2nd level or greater, a paladin's special abilities, and other powers that are granted by the deities. When a greater doppelganger that has already consumed three or more personalities consumes another, it must make a Will save (DC 16) to avoid losing a random personality from those it consumed earlier. In any case, the greater doppelganger cannot have more consumed identities than it has Hit Dice, losing a random identity from its earlier pool if it tries to exceed that limit. If a greater doppelganger "wearing" one of its consumed identities commits an act that runs counter to that form's alignment, it is immediately forced into its base form for 1d10 rounds. In its base form, a greater doppelganger retains the basic memories of all the identities it has consumed, though not deeper memories. Memories from previously consumed identities that have been forced out by new identities fade quickly.

Immunities (Ex): Greater doppelgangers are immune to sleep, charm, and hold effects, as well as all other mind-influencing spells. They are also immune to effects that detect alignment.

Magic Item Use (Ex): No matter what their form, greater doppelgangers can use magic items.

Skills: A greater doppelganger receives a +4 racial bonus on Bluff and Disguise checks. When using alter self a greater doppelganger receives a +10 bonus on Disguise checks. If it can read an opponent's mind, it gets a further +4 competence bonus on Bluff and Disguise checks. A greater doppelganger using alter self to assume an identity that it has consumed using its consume identity ability does not have to make Disguise checks; its control of the consumed personality is complete.

When in its natural form or the guise of someone unarmed, a doppelganger strikes with its powerful fists. In the shape of a warrior or other armed person, it attacks with whatever weapon is appropriate. In such cases, it uses its detect thoughts ability to employ the same tactics and strategies as the person it is impersonating.

Shapechanger Subtype

A shapechanger has the supernatural ability to assume one or more alternate forms. Many magical effects allow some kind of shape shifting, and not every creature that can change shapes has the shapechanger subtype.

Traits: A shapechanger possesses the following traits (unless otherwise noted in a creature's entry).