Deep One Archimandrite

Amphibious. A deep one can breathe air or water with equal ease.

Frenzied Rage. On its next turn after a deep one archimandrite takes 10 or more damage from a single attack, it has advantage on its attacks, it adds +4 to damage, and it can make one extra unholy trident attack.

Innate Spellcasting. the deep one archimandrite's innate spellcasting ability is Charisma (spell save DC 15, +7 to hit with spell attacks). It can innately cast the following spells, requiring no material components: at will: bless, revivify, sacred flame, shocking grasp, suggestion 3/day each: charm person, lightning bolt, sanctuary, shatter 1/day each: chain lightning, cone of cold, ice storm

Legendary Resistance (1/Day). If the deep one archimandrite fails a saving throw, it can count it as a success instead.

Lightless Depths. A deep one hybrid priest is immune to the pressure effects of the deep ocean.

Voice of the Archimandrite. With a ringing shout, the deep one archimandrite summons all deep ones within a mile to come to his aid. This is not a spell but a command that ocean creatures and deep ones heed willingly.

Multiattack. A deep one archimandrite makes one claw attack and 1 unholy trident attack.

Claw. Melee Weapon Attack. +8 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 5) slashing damage.

Unholy Trident. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 14 (2d8 + 5) piercing damage plus 13 (2d12) necrotic damage.