Golem, Mud (CR 11)

Large Construct
Alignment: Always neutral
Initiative: -1 (Dex)
Languages: Cannot speak

AC: 21 (-1 size, -1 Dex, +13 natural), touch 8, flat-footed 21
Hit Dice: 15d10+30 (112 hp); DR: 10/adamantine and bludgeoning
Fort +5, Ref +4, Will +5
Speed: 20 ft. (cannot run), swim 20 ft.
Space: 10 ft./10 ft.
Base Attack +11; Grapple +22
Attack: Slam +17 melee
Full Attack: 2 slams +17 melee
Damage: Slam 2d10+7
Special Attacks/Actions: Breath weapon, engulf
Abilities: Str 24, Dex 9, Con -, Int -, Wis 11, Cha 1
Special Qualities: Construct traits, immunity to magic
Feats: -
Skills: Hide -5* and Swim +15
Advancement: 16-22 HD (Large); 23-30 HD (Huge)
Climate/Terrain: Any
Organization: Solitary or gang (2-4)
Treasure/Possessions: None

Source: Monster Manual III

Breath Weapon (Su): Once every 1d4 rounds of combat, a mud golem can spray slippery mud in a 15-foot cone as a free action. This spray deals no damage, but any creature within the area that fails a Reflex save (DC 16) is blinded for round. In addition, this mud is very slippery. Any creature moving in the affected area must make a Balance check (DC 16) or fall prone. The mud remains slippery for 1 hour before it dries out. Mud golems are immune to the blinding and slippery effects of their own and other mud golems' breath weapons.

Construct: Immune to mind-influencing effects, poison, disease, and similar effects. Not subject to critical hits, subdual damage, ability damage, energy drain, or death from massive damage.

Engulf (Ex): If a mud golem successfully grapples a creature of a smaller size category, it engulfs it with its mass. While engulfed, there is a chance the opponent will begin to drown (see Drowning). An engulfed character must make a Constitution check (DC 20) to successfully hold his breath before being engulfed.

While engulfed, the character cannot attack the mud golem, cast a spell, or use any supernatural or spell-like ability. The all-encompassing mud and the magic-proof nature of the golem make such efforts futile. The engulfed creature must succeed at an opposed grapple or Escape Artist check (against the mud golem's +18 grapple check). The mud golem can engulf one Medium-sized or two Small opponents at a time. A mud golem does not count as grappled for having engulfed creatures within it.

Immune to Piercing and Slashing Weapons (Ex): Piercing and slashing weapons, even enchanted ones, deal no damage to a mud golem.

Magic Immunity (Ex): A mud golem is immune to all spells, spell-like abilities, and supernatural effects, except as follows. A transmute mud to rock spell slows it (as the slow spell) for 2d6 rounds, with no saving throw, while transmute rock to mud heals all its lost hit points. A stone to flesh spell does not change the golem's structure, but it negates its damage reduction and immunity to piercing and slashing weapons for 1 round.

Mud golems fight best from areas of mud where they can bury themselves in the muck to strike opponents from surprise. Shuffling on to more solid ground when necessary, a mud golem attempts to blind and slow foes with its mud spray and then engulf them.