Gigantura

Telescoping Eyes. Advantage on Wis (Perception) checks that rely on sight and magical darkness doesn't impede its darkvision. Also disadvantage on ability checks and saves vs. being blinded.

Water Breathing. Can breathe only underwater.

Multiattack. Horrific Gaze. Then one Bite and two Tail Slaps.

Bite. Melee Weapon Attack: +11 to hit, 10 ft., one target, 25 (3d12+6) piercing damage. If target is a Huge or smaller creature it must make DC 18 Dex save or be swallowed by gigantura. A swallowed creature is blinded and restrained has total cover vs. attacks and effects outside gigantura and takes 21 (6d6) acid at start of each of gigantura's turns. Gigantura can have up to 2 Huge 4 Large 6 Medium or 8 Small creatures swallowed at one time. If gigantura takes 30+ damage on a single turn from a creature inside it gigantura must make DC 20 Con save at end of that turn or regurgitate all swallowed creatures which fall prone in a space within 10 ft. of gigantura. If gigantura dies swallowed creature is no longer restrained by it and can escape from corpse by using 20' of move exiting prone.

Tail Slap. Melee Weapon Attack: +11 to hit, 15 ft., one target, 17 (2d10+6) bludgeoning damage.

Horrific Gaze. Its telescoping eyes swirl disconcertingly in direction of one creature it can see within 60' of it. If target can see gigantura target stunned until end of its next turn (DC 18 Con negates). A target that successfully saves is immune to this gigantura's Horrific Gaze for the next 24 hrs.