ce large aberration amphibious 

Perception +15; darkvision, tremorsense (imprecise) 30 feet

Languages Aklo, Common (Or Undercommon, for Veimaikhik Variants)

Skills Athletics +17, Nature +13, Stealth +14, Survival +13

Str +6 Dex +3 Con +4 Int +0 Wis +2 Cha -1

AC  28; Fort +18, Ref +15, Will +12

HP 100; Immunities poison

Attack of Opportunity [R]

Speed 30 feet; swim 25 feet

Melee [>] claws +19 (reach 10 feet), Damage 2d8+9 bludgeoning plus Grab

Constrict [>] 1d8+9 bludgeoning, DC 25 (grabbed by claws only)

Mandibles [>] Requirements A creature is grabbed and paralyzed by the chuul's tentacles. Effect The creature takes 3d6 piercing damage.

Paralytic Venom (incapacitation, poison) Saving Throw DC 25 Fortitude; Maximum Duration 6 rounds; Stage 1 paralyzed. (1 round)

Tentacle Transfer [>] Requirements The chuul has a creature grabbed. Effect The chuul transfers the grabbed creature from its claws to its tentacles, or vice versa. A creature is exposed to the chuul's paralytic venom when transferred into the tentacles and at the start of each of the chuul's turns if it remains grabbed by the tentacles.

Bestiary, page 64.