Crawling Slaughter (CR 8)

Gargantuan Undead
Alignment: Always neutral
Initiative: +2 (Dex); Senses: darkvision 60 ft.

AC: 24 (-4 size, +2 Dex, +16 natural), touch 8, flat-footed 22
Hit Dice: 24d12 (156 hp)
Fort +8, Ref +10, Will +14
Speed: 30 ft., climb 20 ft.
Space: 20 ft./15 ft.
Base Attack +12; Grapple +31
Attack: Bite +15 melee
Full Attack: Bite +15 melee or web +9 ranged touch
Damage: Bite 3d6+10, web special
Special Attacks/Actions: Stench, web
Abilities: Str 25, Dex 15, Con -, Int -, Wis 10, Cha 1
Special Qualities: single actions only, undead traits
Feats: -
Skills: Climb +15
Advancement: 25-48 HD (Gargantuan); 49-64 HD (Colossal)
Climate/Terrain: Any land or underground
Organization: Solitary
Treasure: None

Source: Dragon #309

The crawling slaughter is an enormous undead creature created from the remains of a monstrous spider. Although not venomous, the crawling slaughter drips fetid goo from its orifices as it lumbers across the landscape. The creatures horrific stench foretells its approach for hundreds of yards, and it leaves a trail of slime and rotting lumps of flesh behind it.

The crawling slaughter is often found in the company of drow, serving either as the centerpiece of a warband or occasionally as a mount for a powerful drow cleric. In the latter case, the drow commands the creature with a large spiked ankus. A crawling slaughter feels no fear, no joy, no want, and very little pain - it exists only to destroy the enemies of its master.