n medium aberration undead 

Perception +9; darkvision, tremorsense (imprecise) 30 feet

Skills Athletics +12, Stealth +10

Str +5 Dex +2 Con +3 Int -4 Wis +1 Cha -5

AC  20; all-around vision; Fort +14, Ref +11, Will +9

HP 55, negative healing; Immunities poison, death effects, disease, paralyzed; Resistances slashing 5, piercing 5

Speed 20 feet, climb 20 feet, swim 20 feet

Melee [>] fleshy slap +14 (forceful), Damage 2d6+8 bludgeoning plus Grab

Ranged [>] bone shard +11 (agile, range increment 20 feet, versatile p), Damage 1d8+8 bludgeoning

Sapping Squeeze [>] Requirements The shanrigol has a creature grabbed; Effect The shanrigol squeezes the life essence from its target, dealing 1d6+5 bludgeoning and 1d4 persistent bleed damage (DC 18 basic Fortitude save). The shanrigol regains temporary Hit Points equal to half the amount of bludgeoning damage a single target takes; these temporary Hit Points last for 1 minute.

Shred Flesh A shanrigol rips flesh away from targets in great chunks. Creatures critically hit by the shanrigol's fleshy slap Strike take an additional 1d6 persistent bleed damage and are enfeebled 1 for as long as they are bleeding.

Undulating Step [>>] The shanrigol separates its flesh from its bones to fit through small spaces. It Strides, ignoring difficult terrain and fitting through tight spaces as though it were a Tiny creature. It can't use any actions other than Undulating Step until it occupies an area large enough for its normal form.

Abomination Vaults #2: Hands of the Devil, page 84.