Astral Stalker (CR 12)

Medium Outsider (Extraplanar)
Alignment: Always lawful evil
Initiative: +9 (+5 Dex, +4 Improved Initiative); Senses: darkvision 120 ft., scent, Listen +20, and Spot +20

AC: 30 (+5 Dex, +10 natural, +5 deflection), touch 20, flat-footed 25
Hit Dice: 12d8+72 (126 hp); DR: 10/magic
Fort +19, Ref +18, Will +18
Speed: 50 ft., climb 20 ft.
Space: 5 ft./5 ft.
Base Attack +12; Grapple +19
Attack: Claw +20 melee or throat dart +17 ranged
Full Attack: 2 claws +20 melee or throat dart +17 ranged
Damage: Claw 1d6+7/19-20, throat dart 1d4+7 plus poison
Special Attacks/Actions: Poison, sneak attack +2d6, throat dart
Abilities: Str 25, Dex 21, Con 23, Int 12, Wis 16, Cha 20
Special Qualities: Camouflage, elusive prey, evasion, outsider traits, swift tracker, unearthly grace
Feats: Alertness; Improved Critical (claw); Improved Initiative; Improved Natural Attack (claw); Iron Will; Track; Weapon Focus (claw)
Skills: Climb +30, Hide +20, Jump +30, Listen +20, Move Silently +20, Search +16, Sense Motive +18, Spot +20, and Survival +18
Advancement: By character class
Climate/Terrain: Astral Plane
Organization: Solitary or hunting party (2-6)
Treasure/Possessions: Standard

Source: Monster Manual III

Poison (Ex): Injury; Fortitude DC 22; initial damage paralysis 1d4 rounds; secondary damage none. The save DC is Constitution-based.

Sneak Attack (Ex): An astral stalker can make a sneak attack like a rogue, dealing an extra 2d6 points of damage whenever a foe is denied its Dexterity bonus or when the astral stalker is flanking.

Throat Dart (Ex): An astral stalker's throat dart has a range of 150 feet with no range increment.

Camouflage (Ex): An astral stalker can use the Hide skill in any sort of natural terrain, even if the terrain does not grant cover or concealment.

Elusive Prey (Ex): An astral stalker is difficult to track. Anyone trying to track one takes a -10 penalty on Survival checks.

Evasion (Ex): An astral stalker can avoid even magical and unusual attacks with great agility. If it makes a successful Reflex saving throw against an attack that normally deals half damage on a successful save, it instead takes no damage.

Swift Tracker (Ex): An astral stalker can move at its normal speed while following tracks without taking the normal -5 penalty. It takes only a -10 penalty (instead of the normal -20 penalty) when moving at up to twice normal speed while tracking.

Unearthly Grace (Su): An astral stalker adds its Charisma modifier as a bonus on all its saving throws and as a deflection bonus to its Armor Class.

Skills: An astral stalker has a +8 racial bonus on Climb checks and can always choose to take 10 on Climb checks, even if rushed or threatened.

Extraplanar Subtype

A subtype applied to any creature when it is on a plane other than its native plane. A creature that travels the planes can gain or lose this subtype as it goes from plane to plane. This book assumes that encounters with creatures take place on the Material Plane, and every creature whose native plane is not the Material Plane has the extraplanar subtype (but would not have when on its home plane). An extraplanar creatures usually has a home plane mentioned in its description. These home planes are taken from the Great Wheel cosmology of the D&D game (see Chapter 5 of the Dungeon Master's Guide). If your campaign uses a different cosmology, you will need to assign different home planes to extraplanar creatures.

Creatures not labeled as extraplanar are natives of the Material Plane, and they gain the extraplanar subtype if they leave the Material Plane. No creature has the extraplanar subtype when it is on a transitive plane; the transitive planes in the D&D cosmology are the Astral Plane, the Ethereal Plane, and the Plane of Shadow.