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.

Spittle (Ex): As a free action every round, a gibbering mouther fires 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.

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

Blood Drain (Ex): On a successful grapple check after grabbing, that mouth attaches to the opponent. It automatically deals bite damage and drains blood, dealing 1 point of Constitution damage each round. A mouth can be ripped off (dealing 1 point of damage) with a DC 12 Strength check or severed by a successful sunder attempt (the mouth has 2 hit points).

A severed mouth continues to bite and drain blood for 1d4 rounds after such an attack. A creature whose Constitution is reduced to 0 is killed.

Engulf (Ex): A gibbering mouther can try to engulf a Medium or smaller opponent grabbed by three or more mouths.

The opponent must succeed on a DC 14 Reflex save or fall and be engulfed. In the next round, the mouther makes twelve bite attacks instead of six (each with a +4 attack bonus). An engulfed creature cannot attack the mouther from within. The previously attached mouths are now free to attack others. The save DC is Strength-based and includes a +2 racial bonus.

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).

Amorphous (Ex): A gibbering mouther is not subject to 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.