Rejuvenation. If it dies, the naga returns to life in 1d6 days and regains all its hit points. Only a wish spell can prevent this trait from functioning.
Spellcasting. The naga is an 11th-level spellcaster. Its spellcasting ability is Wisdom (spell save DC 16, +8 to hit with spell attacks), and it needs only verbal components to cast its spells. It has the following cleric spells prepared:
Cantrips (at will): mending, sacred flame, thaumaturgyBite. Melee Weapon Attack: +8 to hit, reach 10 ft., one creature. Hit: 8 (1d8 + 4) piercing damage, and the target must make a DC 15 Constitution saving throw, taking 45 (10d8) poison damage on a failed save, or half as much damage on a successful one.
Spit Poison. Ranged Weapon Attack: +8 to hit, range 15/30 ft., one creature. Hit: The target must make a DC 15 Constitution saving throw, taking 45 (10d8) poison damage on a failed save, or half as much damage on a successful one.