Armor Class 12 (natural armor)
Hit Points 114 (12d12 + 36)
Speed swim 50 ft.
Saving Throws STR +8, CON +6
Skills Athletics +8, Perception +5
Senses darkvision 120 ft., passive Perception 15
Languages Sahuagin, telepathy 100 ft.
Challenge 7
Legendary Resistance (2/Day). If the maw of Sekolah fails a saving throw, it can choose to succeed instead.
Water Breathing. The maw of Sekolah can breathe only underwater.
Multiattack. The maw of Sekolah makes one attack with its bite and one attack with its tail smash.
Bite. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 16 (2d10 + 5) piercing damage.
Tail Smash. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 9 (1d8 + 5) bludgeoning damage.
Detect. The maw of Sekolah makes a Wisdom (Perception) check.
Speed of Sekolah. The maw of Sekolah moves up to its speed.
Feed (Costs 2 Actions). The ferocious spirit of Sekolah flashes through the water, tearing through the foes of the maw of Sekolah. Each creature of the maw's choosing within 60 feet of it must make a DC 16 Dexterity saving throw, taking 7 (2d6) slashing damage on a failed save, or half as much damage on a successful one.
GoS, p. 244