Earthcancer Centipede (CR 13)

Gargantuan Undead
Alignment: Always neutral evil
Initiative: +8 (+4 Dex, +4 Improved Initiative); Senses: darkvision 60 ft., tremorsense 120 ft., Listen +27, and Spot +0

AC: 30 (-4 Size, +4 Dex, +15 natural, +5 haste), touch 15, flat-footed 26
Hit Dice: 24d12 (156 hp); DR: 15/silver
Fort +10, Ref +14, Will +16
Speed: 60 ft., burrow 60 ft.
Space: 20 ft./15 ft.
Base Attack +12; Grapple +33
Attack: 2 bites +17 melee
Full Attack: 2 bites +17 melee
Damage: 2 bites 4d6+13/19-20 plus poison
Special Attacks/Actions: earthcancer aura 60 ft.
Abilities: Str 18, Dex 18, Con -, Int 2, Wis 10, Cha 14
Special Qualities: Alacrity, obey the wormtouched, undead traits, fast healing 10;
Feats: Combat Reflexes; Dodge; Great Fortitude; Improved Critical (bite); Improved Initiative; Iron Will; Lightning Reflexes; Mobility; Spring Attack
Skills: Listen +27 and Spot +0
Advancement: 25-32 HD (Gargantuan), 33-72 HD (Colossal)
Climate/Terrain: Wormcrawl Fissure
Organization: Solitary, pair, or brood (3-12)
Treasure/Possessions: None

Source: Dungeon #134

Alacrity (Su): An earthcancer centipede moves and attacks with supernatural swiftness. It has a +5 haste bonus to its Armor Class, and a +30 ft. enhancement bonus to its land speed and burrow speed. It may make two bite attacks as a standard action.

Earthcancer Aura (Su): The earthcancer centipede is surrounded by an aura of supernatural energy that invades and corrupts nearby earth and stone. Leprous growths of rancid fungi and aberrant rock formations writhe out of any stony or earthen surface within 60 feet of an earthcancer centipede. This condition does not alter the structural integrity of the surrounding stone, and thus does not damage structures. It does count as difficult terrain to move through. Additionally, contact with the tainted earth and stone nauseates living creatures. Any creature who touches this tainted earth or stone (including those who walk upon it) must make a DC 24 Fortitude save each round to avoid becoming nauseated for that round. Creatures with the earth subtype within 60 feet of an earthcancer centipede must also make a DC 24 Fortitude save each round to avoid taking 1d6 points of Constitution damage. The save DC is Charisma-based.

Poison (Ex): Injury, Fortitude DC 24, initial and secondary damage 3d6 Dexterity drain. The save DC is Charisma-based.

Obey the Wormtouched (Ex): Although it is nearly mindless, an earthcancer centipede unerringly follows simple commands given by other undead servants of Kyuss.

In combat, an earthcancer centipede uses its supernatural strength to great effect, scuttling and burrowing into the midst of its enemies and biting with horrifying rapidity. They have an instinctive swarming technique that often sets them up for flanking attacks against creatures they surround, although they just as often spread out their attacks on any targets within reach.

Earthcancer centipedes are the result of Kyuss' attempt to generate undead useful in sieges. An earthcancer centipede is thirty-five feet long and weighs 18 tons.