Amphibious. The kuo-toa can breathe air and water.
Otherworldly Perception. The kuo-toa can sense the presence of any creature within 30 feet of it that is invisible or on the Ethereal Plane. It can pinpoint such a creature that is moving.
Slippery. The kuo-toa has advantage on ability checks and saving throws made to escape a grapple.
Sunlight Sensitivity. While in sunlight, the kuo-toa has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight.
Spellcasting. The kuo-toa is a 10th-level spellcaster. Its spellcasting ability is Wisdom (spell save DC 14, +6 to hit with spell attacks). The kuo-toa has the following cleric spells prepared:
Cantrips (at will): guidance, sacred flame, thaumaturgy
1st level (4 slots): detect magic, sanctuary, shield of faith
2nd level (3 slots): hold person, spiritual weapon
3rd level (3 slots): spirit guardians, tongues
4th level (3 slots): control water, divination
5th level (2 slots): mass cure wounds, scrying
Multiattack. The kuo-toa makes two melee attacks.
Scepter. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit:6 (1d6 + 3) bludgeoning damage plus 14 (4d6) lightning damage.
Unarmed Strike. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit:5 (1d4 + 3) bludgeoning damage.
Kuo-toa are degenerate fishlike humanoids that once inhabited the shores and islands of the surface world. Long ago humans and their ilk drove the kuo-toa underground, where they dwell in madness and everlasting night. Kuo-toa can no longer abide daylight.