Xenostelid (CR 17)

Huge Aberration
Alignment: Usually chaotic evil
Initiative: +2; Senses: darkvision 60 ft., Listen +29, and Spot +29
Languages: Daelkyr, Undercommon

AC: 30 (-2 size, +2 Dex, +20 natural), touch 10, flat-footed 28
Hit Dice: 23d8 (310 hp); DR: 15/byshek
Fort +16, Ref +9, Will +16
Speed: 60 ft., climb 30 ft.
Space: 15 ft./15 ft.
Base Attack +17; Grapple +36
Attack: 4 claws +24 melee and bite +22 melee
Damage: 4 claws melee 2d6+11/18-20/x3, bite melee 2d6+16 plus poison
Special Attacks/Actions: Awesome Blow, Cleave, Improved Bull Rush, Improved Sunder, Power Attack, adamantine strike, augmented critical, poison (DC 36; 1d6 Str, Dex, Con; 1d6 Str, Dex, Con), rend 6d6+19, screech (DC 30; 11d6), web (DC 30)
Abilities: Str 33, Dex 14, Con 29, Int 10, Wis 17, Cha 14
Special Qualities: fast healing 5; Immune to mind-affecting effects, poison; SR 25
Feats: Awesome Blow, Cleave, Improved Bull Rush, Improved Initiative, Improved Natural Attack (claw), Improved Sunder, Multiattack, Power Attack
Skills: Climb +19, Jump +23, Listen +29, and Spot +29
Advancement: 19-36 HD (Huge), 37-54 HD (Gargantuan)
Climate/Terrain: Any land and underground (Eberron)
Organization: Solitary or mated pair
Treasure/Possessions: Standard

Source: Dragon #348

Poison (Ex) The venom of the xenostelid combines all the most painful aspects of the venom of spiders, centipedes, and scorpions. Fortitude DC 30 negates; initial damage 1d6 Str, 1d6 Dex, and 1d6 Con; secondary damage 1d6 Str, 1d6 Dex, and 1d6 Con.

Adamantine Strike (Ex) A xenostelid's claws count as adamantine weapons for the purposes of overcoming damage reduction and hardness.

Augmented Critical (Ex) A xenostelid's claw attacks threaten a critical hit on a roll of 18-20, dealing x3 damage on a successful critical hit.

Rend (Ex) When a xenostelid hits an opponent with multiple claw attacks, it grabs and tears the flesh. For every two claws that hit a single opponent, the xenostelid deals an extra 6d6+18 damage.

Screech (Su) Three times per day, but no more than once every 1d4 rounds, a xenostelid can emit a horrible shriek as a move action, dealing 11d6 points of sonic damage to all creatures and unattended objects in a 60-foot radius. A DC 30 Fortitude save halves the damage. The save DC is Constitution-based.

Web (Ex) A xenostelid can throw a web eight times per day. This is similar to an attack with a net but has a maximum range of 100 feet, with a range increment of 20 feet, and is effective against targets up to Gargantuan size. The web anchors the target in place, trapping the target in its current space.

An entangled creature can escape with a DC 30 Escape Artist check, or a DC 34 Strength check. The check DC is Constitution-based, and the Strength check DC includes a +4 racial bonus. The web has 30 hit points, hardness 5, and takes double damage from fire.

The xenostelid can also create sheets of sticky webbing that coats up to 20 squares (it can choose to coat less). An approaching creature must make a DC 20 Spot check to notice a web or else it stumbles into the web and becomes trapped. Attempts to escape or burst the webbing receive a +5 bonus if the trapped creature has something to walk on or grab while pulling free. Each 5-foot-square section of webbing has 30 hit points, hardness 5, and takes double damage from fire.

A xenostelid can move across its own sheet web at its climb speed and can determine the exact location of any creature touching the web.

Skills A xenostelid receives a +8 racial bonus on Climb checks and can always take 10 on a Climb check, even if rushed or threatened.