Ethereal Slayer (CR 12)

Medium Outsider
Alignment: Always chaotic evil
Initiative: +8 (+4 Dex, +4 Improved Initiative); Senses: Listen +24 and Spot +24

AC: 24 (+4 Dex, +10 natural), touch 14, flat-footed 20
Hit Dice: 16d8+32 (104 hp); DR: 10/magic
Fort +12, Ref +14, Will +13
Speed: 50 ft.
Space: 5 ft./10 ft.
Base Attack +16; Grapple +17
Attack: Claw +21 melee
Full Attack: 2 claws +21 melee and bite +15 melee
Damage: Claw 1d8+1, bite 1d6
Special Attacks/Actions:
Abilities: Str 12, Dex 19, Con 14, Int 5, Wis 16, Cha 9
Special Qualities: Detect magic, dimensional anchor, outsider traits, plane shift, SR 23
Feats: Alertness; Dodge; Improved Initiative; Mobility; Weapon Finesse; Weapon Focus (claw)
Skills: Hide +23, Jump +28, Listen +24, Move Silently +23, and Spot +24
Advancement: 17-24 HD (Medium-size); 25-32 HD (Large); 33-40 HD (Huge); 41-48 HD (Gargantuan)
Climate/Terrain: Any
Organization: Solitary
Treasure/Possessions: None

Source: Monster Manual II

Detect Magic (Su): An ethereal slayer can produce a detect magic effect (caster level 9th) at will.

Dimensional Anchor (Su): An ethereal slayer can produce a dimensional anchor effect (caster level 9th) at will.

Outsider Traits: An ethereal slayer has darkvision (60 ft. foot range). It cannot be raised or resurrected.

Plane Shift (Su): Twice per day, an ethereal slayer can produce a plane shift effect (caster level 9th; self only, save DC 14).