Blindsight (Ex): A sewer sludge is blind but can ascertain all creatures and objects within 30 feet just as a sighted creature would. Beyond that range, all targets have total concealment with respect to the sewer sludge.
Camouflage (Ex): A motionless sewer sludge looks like nothing more than a pile of rotting garbage. A successful Spot check (DC 15) is required to recognize it as a creature.
Constrict (Ex): A sewer sludge deals slam damage (1d6+1 for a typical specimen) with a successful grapple check against a target at least one size category smaller than itself.
Disease (Ex): The touch of a sewer sludge carries typhoid bacillus (Fort DC 13 negates; incubation period 1d3 weeks; initial 1d4 Con; secondary 1d4 Con).
Immunities (Ex): A sewer sludge is immune to electricity and cold damage. If a cold attack deals damage equal to or greater than the sewer sludge’s Constitution score, the creature is affected as though by a slow spell.
Improved Grab (Ex): To use this ability, the sewer sludge must hit an opponent at least one size category smaller than itself with its slam attack. If it gets a hold, it automatically deals slam damage each round that the hold is maintained, and it can constrict in the same round.
Ooze: A sewer sludge has the traits and immunities common to oozes.
Stench (Ex): A creature within 10 feet of a sewer sludge must make a successful Fortitude save (DC 10 + 1/2 the sludge’s Hit Dice + its Constitution modifier) or be nauseated. The nausea persists for as long as the creature remains within 10 feet of the sewer sludge. A creature that leaves and reenters the area must make another save.
Sewer Sludge: CR 5; Medium-size ooze; HD 4d10+14; hp 36; Mas —; Init +0; Spd 20 ft.; Defense 10, touch 10, flat-footed 10; BAB +3; Grap +4; Atk +4 melee (1d6+1 plus disease, slam); Full Atk +4 melee (1d6+1 plus disease, slam); FS 5 ft. by 5 ft.; Reach 5 ft.; SQ blindsight 30 ft., disease, camouflage, constrict 1d6+1, immunities, improved grab, ooze, stench (DC 13); AL none; SV Fort +2, Ref +1, Will –4; AP 0; Rep +0; Str 13, Dex 10, Con 13, Int —, Wis 1, Cha 1.
Advancement: 5–8 HD (Large); 9–12 HD (Huge).
Advanced Sewer Sludge: CR 7; Large ooze; HD 8d10+39; hp 83; Mas —; Init +0; Spd 20 ft.; Defense 10, touch 8, flatfooted 10 (–1 size, –1 Dex, +2 natural); BAB +6; Grap +15; Atk +10 melee (1d8+7 plus disease, slam); Full Atk +10/+5 melee (1d8+7 plus disease, slam); FS 10 ft. by 10 ft.; Reach 10 ft.; SQ blindsight 30 ft., disease, camouflage, constrict 1d6+1, immunities, improved grab, ooze, stench (DC 17); AL none; SV Fort +5, Ref +1, Will –3; AP 0; Rep +0; Str 21, Dex 8, Con 17, Int —, Wis 1, Cha 1.