Reigar

The reigar's Armor Class includes its Charisma modifier.

The reigar can hold its breath for 1 hour.

The reigar wears a talarith.

The reigar casts one of the following spells, requiring no spell components and using Charisma as the spellcasting ability (spell save DC 18):

At will: light, mage hand, prestidigitation

2/day each: dimension door, phantasmal force

1/day each: mass suggestion, sending

The reigar makes two Trident attacks.

Melee or Ranged Weapon Attack: +7 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 7 (1d6 + 4) piercing damage, or 8 (1d8 + 4) piercing damage if used with two hands to make a melee attack, plus 3 (1d6) force damage if the reigar is wearing its talarith.

Ranged Spell Attack: +10 to hit, range 90 ft., one target. Hit: 22 (5d8) damage of a type chosen by the reigar from the following list: cold, fire, lightning, or radiant.

Using its talarith, the reigar summons a duplicate of itself. The duplicate obeys the reigar's commands and uses the reigar's statistics, except it is an unaligned Construct that doesn't have a talarith of its own. The duplicate takes its turn immediately after the reigar. It vanishes after 1 hour or when it is reduced to 0 hit points.