Shadestriker (CR 2)

Tiny Magical Beast
Alignment: Always Neutral Evil
Initiative: +9 (+5 Dex, Improved Initiative)

AC: 18 (+2 size, +5 Dex, +1 natural), touch 17, flat-footed 13
Hit Dice: 2d10 (15 hp)
Fort +5, Ref +8, Will +1
Speed: 10 ft., fly 80 ft. (average)
Space: 2 1/2 ft./0 ft.
Base Attack +2; Grapple -8
Attack: talons +2 melee (1d2-2), needlespike +7 ranged (1d4)
Special Attacks/Actions: Needlespike, sneak attack +1d6
Abilities: Str 6, Dex 20, Con 14, Int 6, Wis 12, Cha 12
Special Qualities: SR 14, blood trace
Feats: Improved Initiative, Track
Skills: Hide +5, Move Silently +5, and Survival +6
Advancement: 3-6 HD (Small)
Climate/Terrain: Any underground
Organization: Solitary or with master (Drow), understands Drow.
Treasure/Possessions: None

Source: Dragon #357

Needlespike (Ex): Like many birds, shadestrikers swallow small pebbles and stones as an aid to their digestion. Unlike most birds, however, they use stomach contractions and powerful digestive juices to gradually turn these stones into razor sharp missiles. Three times per day, a shadestalker can spit a cluster of these needlespikes as ranged attacks (range increment 20 feet).

Sneak Attack (Ex): Whenever a shadestriker's opponent is denied his Dexterity bonus to AC, or if the shadestriker flanks its opponent, it deals an extra 1d6 points of damage. This ability is just like a rogue's sneak attack and subject to the same limitations.

Blood Trace (Ex): A shadestriker gains a +10 bonus on Survival checks made to tracking creatures wounded or otherwise covered in blood.

Skills: Shadestrikers gain a +5 bonus on Hide and Move Silently checks made in subterranean environments.