Gorgahydra* (CR 12)

Large Magical Beast
Alignment: Always chaotic neutral
Initiative: +4; Senses: darkvision 90 ft., low-light vision, scent, Listen +29, and Spot +29

AC: 25 (-1 size, +16 natural), touch 9, flat-footed 25
Hit Dice: 22d10+220 (341 hp)
Fort +23, Ref +13, Will +8
Speed: 30 ft.
Space: 5 ft./5 ft.
Base Attack +22; Grapple +22
Attack: 8 gores +26 melee
Full Attack: 8 gores +26 melee
Damage: gore 1d8+5
Special Attacks/Actions: Breath weapon (60-ft. cone of petrification gas), trample 1d8+7
Abilities: Str 21, Dex 10, Con 31, Int 2, Wis 12, Cha 9
Special Qualities:
Feats: Alertness; Cleave; Great Cleave; Improved Critical (gore); Improved Initiative; Power Attack
Skills: Listen +29, Search +10, and Spot +29
Advancement: -
Climate/Terrain: Temperate and warm land and underground
Organization: Solitary
Treasure/Possessions: None

Source: Web

Breath Weapon (Su): Each of a gorgahydra's eight heads can create a 60- foot cone of petrifying gas every 1d4 rounds that permanently turns its victim to stone (Fortitude DC 31). Though the gorgahydra has eight heads, it cannot use its breath weapon more than five times each day, total.

Trample: A gorgahydra can trample Small or smaller creatures for 1d8+7 points of damage. Opponents who do not make attacks of opportunity against the gorgahydra can attempt a reflex save (DC 26) to halve the damage.

Low-Light Vision: The creature can see twice as far as a human in starlight, moonlight, torchlight, and similar low-light conditions.

Scent (Ex): The creature can detect approaching enemies, sniff out hidden foes, and track by sense of smell.