uncommon ce gargantuan beast 

Perception +28; darkvision, scent (imprecise) 60 feet

Languages Aquan, Draconic, Tratrith

Skills Athletics +34, Intimidation +28, Nature +26, Stealth +23

Str +9 Dex +5 Con +8 Int +5 Wis +6 Cha +0

Deep Breath A grootslang can hold its breath for 1 hour.

AC  38; Fort +30, Ref +27, Will +26

HP 370

Attack of Opportunity [R]

Speed 40 feet, swim 30 feet

Melee [>] foot +30 (magical, reach 20 feet), Damage 3d12+15 bludgeoning

Melee [>] jaws +28 (agile, magical, reach 15 feet), Damage 3d10+15 piercing plus Improved Grab

Melee [>] tail +28 (agile, magical, reach 30 feet), Damage 3d10+15 bludgeoning plus Grab

Melee [>] tusk +30 (magical, reach 20 feet), Damage 3d12+15 piercing

Aquatic Elusion [>>] (concentrate, conjuration, teleportation, primal) Requirements The grootslang is fully immersed in water; Effect The grootslang teleports to another body of water within 1 mile that is wide enough to hold the grootslang.

Defensive Coil [>>] The grootslang coils its body. It gains 20 resistance against physical attacks until the start of its next turn.

Greater Constrict [>] tail only, 2d12+12 bludgeoning, DC 34

Swallow Whole [>] jaws only, Huge, 3d12+10 bludgeoning, Rupture 37.

Thunderous Slam [>>>] The grootslang makes a foot Strike against a creature in reach. Whether or not the Strike hits, all creatures within 10 feet of the grootslang must attempt a DC 37 Reflex save. Critical Success The creature is unaffected.Success The creature is flat-footed until the end of its turn.Failure The creature is knocked prone and takes 2d8 bludgeoning damage.Critical Failure As failure, except the creature takes 4d8 bludgeoning damage.

LOME, page 298.