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 2nd-level spellcaster. Its spellcasting ability is Wisdom (spell save DC 12, +4 to hit with spell attacks). The kuo-toa has the following cleric spells prepared:
Cantrips (at will): sacred flame, thaumaturgyMultiattack. The kuo-toa makes two attacks: one with its bite and one with its pincer staff.
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 4 (1d4 + 2) piercing damage.
Pincer Staff. Melee Weapon Attack: +4 to hit, reach 10 ft., one target. Hit: 5 (1d6 + 2) piercing damage. If the target is a Medium or smaller creature, it is grappled (escape DC 14). Until this grapple ends, the kuo-toa can't use its pincer staff on another target.
A kuo-toa monitor has a challenge rating of 3 (700 XP). It has the same statistics as a kuo-toa whip except that it adds its Wisdom modifier to its Armor Class (AC 13), loses the Spellcaster trait, and replaces the whip's action options with the following action options.
Multiattack. The kuo-toa makes one bite attack and two unarmed strikes.
Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 4 (1d4 + 2) piercing damage.
Unarmed Strike. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) bludgeoning damage plus 3 (1d6) lightning damage, and the target can't take reactions until the end of the kuo-toa's next turn.