Gibbering Mouther (CR 5)

Medium Aberration
Alignment: Usually neutral
Initiative: +1 (Dex); Senses: darkvision 60 ft., Listen +4, and Spot +9

AC: 19 (+1 Dex, +8 natural), touch 11, flat-footed 18
Hit Dice: 4d8+24 (42 hp); DR: 5/bludgeon
Fort +7, Ref +4, Will +5
Speed: 10 ft., swim 20 ft.
Space: 5 ft./5 ft.
Base Attack +3; Grapple +3
Attack: Bite +4 melee or spittle +4 ranged touch
Full Attack: 6 bites +4 melee and spittle +4 ranged touch
Damage: Bite 1, spittle 1d4 acid plus blindness
Special Attacks/Actions: Blood drain, gibbering, ground manipulation, improved grab, spittle, swallow whole
Abilities: Str 10, Dex 13, Con 22, Int 4, Wis 13, Cha 13
Special Qualities: Amorphous
Feats: Lightning Reflexes; Weapon Finesse
Skills: Listen +4, Spot +9, and Swim +8
Advancement: 5-12 HD (Large)
Climate/Terrain: Underground
Organization: Solitary
Treasure/Possessions: None

Source: Lords of Madness

Gibbering (Su): As soon as a mouther spots something edible, it begins a constant gibbering as a free action. All creatures (other than mouthers) within a 60-foot spread must succeed on a DC 13 Will save or be affected as though by a confusion spell for 1d2 rounds. This is a sonic mind-affecting compulsion effect. A creature that successfully saves cannot be affected by the same gibbering mouther's gibbering for 24 hours. The save DC is Charisma-based.

Ground Manipulation (Su): At will, as a standard action, a gibbering mouther can cause stone and earth in all adjacent squares to become a morass akin to quicksand. Softening earth, sand, or the like takes 1 round, while stone takes 2 rounds. Anyone other than the mouther in that area must take a move-equivalent action to avoid becoming mired (treat as being pinned).

Improved Grab (Ex): To use this ability, a gibbering mouther must hit a Medium or smaller foe with a bite attack. It can then attempt to start a grapple as a free action without provoking an attack of opportunity.

Swallow Whole (Ex): The gibbering mouther can attempt to swallow a grappled opponent of Medium or smaller size by making a successful grapple check. (The gibbering mouther doesn't actually ""swallow"" the opponent - it engulfs it within its amorphous form - but the effect is essentially the same.) Once inside, the gibbering mouther can use its blood drain ability. A swallowed creature can cut its way out by dealing 5 points of damage to the gibbering mouther (same AC). The gibbering mouther's body can hold 1 Medium, 2 Small, 8 Tiny, 32 Diminutive, or 128 Fine creatures.

Blood Drain (Ex): A swallowed opponent automatically takes 1d4 points of Constitution damage each round.

Spittle (Ex): As a free action every round, a gibbering mouther can fire a stream of spittle at one opponent within 30 feet. The mouther makes a ranged touch attack; if it hits, it deals 1d4 points of acid damage, and the target must succeed on a DC 18 Fortitude save or be blinded for 1d4 rounds. Eyeless creatures are immune to the blinding effect but are still subject to the acid damage. The save DC is Constitution-based.

Amorphous (Ex): A gibbering mouther is not subject to extra damage from critical hits. It cannot be flanked.

Skills: Thanks to their multiple eyes, gibbering mouthers have a +4 racial bonus on Spot checks. A gibbering mouther has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. It always can choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.

A gibbering mouther attacks by shooting out strings of protoplasmic flesh, each ending in one or more eyes and a mouth that bites at the enemy. A mouther can send our a total of six such members in any round.