Multiattack

The lunarchidna makes three attacks: one with its bite and two with its claws.

Bite

Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 3) necrotic damage. The target must succeed on a DC 13 Constitution saving throw or its hp maximum is reduced by an amount equal to the damage taken. This reduction lasts until the target finishes a long rest. The target dies if this effect reduces its hp maximum to 0.

Claw

Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 8 (2d4 + 3) slashing damage.

Web (Recharge 5-6)

Ranged Weapon Attack: +6 to hit, range 30/60 ft., one creature. Hit: The target is restrained by webbing. As an action the restrained target can make a DC 13 Strength check, bursting the webbing on a success. The webbing can also be attacked and destroyed (AC 10; hp 5; vulnerability to fire damage; immunity to bludgeoning, poison, and psychic damage).

Lunar Beam (Recharge 5-6)

The lunarchidna flashes a beam of moonlight in a 30-foot line that is 5 feet wide. Each creature in that line must make a DC 15 Dexterity saving throw, taking 28 (8d6) radiant damage on a failed save, or half as much damage on a successful one.