Multiattack

The koralk makes one Bite attack, one Scythe attack, and three Stinger attacks. It can replace its Scythe attack with a Vestigial Arms attack.

Bite

Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 5) piercing damage.

Scythe

Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 16 (2d10 + 5) slashing damage.

Stinger

Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 7 (1d4 + 5) piercing damage plus 7 (2d6) poison damage, and the target must succeed on a DC 17 Constitution saving throw or succumb to the devil's venom (see the Harvester Venom trait).

Vestigial Arms

Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: If the target is a Medium or smaller creature, it is grappled (escape DC 17). Until this grapple ends, the creature is restrained, and the devil can't use its Vestigial Arms on another target.