Ironclad Mauler (CR 9)

Large Magical Beast
Alignment: Usually neutral evil
Initiative: +1 (Dex); Senses: darkvision 60 ft., low-light vision, Listen +10, and Spot +10

AC: 22 (-1 size, +1 Dex, +7 natural, +5 armor), touch 10, flat-footed 21
Hit Dice: 15d10+75 (157 hp)
Fort +14, Ref +10, Will +6
Speed: 40 ft.
Space: 10 ft./5 ft. (claws up to 10 ft.)
Base Attack +15; Grapple +30
Attack: Claw +26 melee
Full Attack: 2 claws +26 melee and bite +20 melee
Damage: Claw 2d6+11, bite 4d6+5
Special Attacks/Actions: Improved grab, sickening aura, trample 2d6+11
Abilities: Str 33, Dex 13, Con 21, Int 2, Wis 12, Cha 10
Special Qualities: grafted armor, light fortification
Feats: Cleave; Great Cleave; Improved Natural Attack (bite); Improved Natural Attack (claw); Power Attack; Weapon Focus (claw)
Skills: Listen +10 and Spot +10
Advancement: 16-30 HD (Large); 31-45 HD (Huge)
Climate/Terrain: Any
Organization: Solitary or squad (2-5)
Treasure/Possessions: None

Source: Monster Manual III

Improved Grab (Ex): to use this ability, an ironclad mauler must hit with a claw attack. It can then attempt to start a grapple as a free action without provoking attacks of opportunity.

Sickening Aura (Su): an ironclad mauler is surrounded by a field of negative energy. Any creature that comes within 10 feet of an ironclad mauler must make a DC 22 fortitude save or become sickened. This condition lasts for 1 hour. A creature that succeeds on the saving throw is immune to that creature's aura for 24 hours. Undead and constructs are immune to this aura. The save is constitution-based.

Trample (Ex): reflex half DC 28. The save DC is strength-based.

Grafted Armor (Ex): ironclad maulers wear armor that has been magically grafted to their forms. This armor provides significant protection in combat, but it imposes no maximum dexterity bonus, no movement penalty, and no arcane spell failure chance. Other creatures, even other ironclad maulers, cannot wear an ironclad mauler's armor.

Light Fortification (Ex): an ironclad mauler's grafted armor protects its vital areas and makes it resistant to extra damage from critical hits and sneak attacks. Anytime an ironclad mauler is hit by a critical hit or a sneak attack, it has a 25% chance to resist the extra damage.

As their name implies, ironclad maulers were created specifically for war. As such, they relish combat, and rush into melee without hesitation or mercy. Ironclad maulers like nothing more than using their size and strength to smash formations of weaker creatures, but they also seem to enjoy close-fought duels with equally powerful creatures. Unlike natural animals, ironclad maulers never flee a fight. Their innate ferocity and the magical forces used to create them push them to fight to the death in every combat. Although they have only animal intelligence, ironclad maulers instinctively trample groups of smaller creatures in close proximity to one another.