Antimagic Cone. The yuan-holder's primary eye creates an area of antimagic, as in the antimagic field spell, in a 150-foot-cone. At the start of each of its turns, the yuan-holder decides which way the cone faces and whether the cone is active. The area works against the yuan-holder's own eye rays.

Innate Spellcasting. The yuan-holder’s innate spellcasting ability is Charisma (spell save DC 17). The yuan-holder can innately cast the following spells, requiring no material components:

At will: animal friendship (snakes only)

3/day: suggestion

1/day: fear

Legendary Resistance (3/Day). If the yuan-holder fails a saving throw, it can choose to succeed instead.

Magic Resistance. The yuan-holder has advantage on saving throws against spells and other magical effects.

Reactive. The yuan-holder can take one reaction on every turn in a combat if it is wielding a melee weapon.

Multiattack. The yuan-holder use its bite and constrict attacks or its uses Eye Rays.

Bite. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 19 (4d6 + 5) piercing damage.

Constrict. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 14 (2d8 + 5) bludgeoning damage, and the target is grappled (escape DC 18). Until this grapple ends, the target is restrained, and the yuan-holder can’t constrict another target.

Eye Rays. The yuan-holder shoots three of the following magical eye rays at random (reroll duplicates), choosing one to three targets it can see within 120 feet of it:

1. Charm Ray. The targeted creature must succeed on a DC 16 Wisdom saving throw or be charmed by the yuan-holder for 1 hour, or until the yuan-holder harms the creature.
2. Paralyzing Ray. The targeted creature must succeed on a DC 16 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
3. Slowing Ray. The targeted creature must succeed on a DC 16 Dexterity saving throw. On a failed save, the target’s speed is halved for 1 minute. In addition, the creature can’t take reactions, and it can take either an action or a bonus action on its turn, not both. The creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
4. Enervation Ray. The targeted creature must make a DC 16 Constitution saving throw, taking 36 (8d8) necrotic damage on a failed save, or half as much damage on a successful one.
5. Petrification Ray. The targeted creature must make a DC 16 Dexterity saving throw. On a failed save, the creature begins to turn to stone and is restrained. It must repeat the saving throw at the end of its next turn. On a success, the effect ends. On a failure, the creature is petrified until freed by the greater restoration spell or other magic.
6. Lightning Ray. The targeted must succeed on a DC 16 Dexterity saving throw, taking 27 (6d8) lightning damage.  The lightning jumps from the target to two secondary creatures of the yuan-holder's choice that it can see within 30 feet of the target. Those secondary creatures must succeed on a DC 16 Dexterity saving throw or take 13 (3d8) lightning damage.

Psychic Scream. Each creature of the yuan-holder's choice that is within 120 feet of the aberration and aware of it must succeed on a DC 16 Wisdom saving throw or become stunned until the end of its next turn. If a creature's saving throw is successful, the creature is immune to the yuan-holder's Psychic Scream for the next 24 hours.

Parry. The yuan-holder adds 5 to its AC against one melee attack that would hit it. To do so, the yuan-holder must see the attacker and be wielding a melee weapon.

The yuan-holder can take 3 legendary actions, using the Eye Ray option below. It can take only one legendary action at a time and only at the end of another creature’s turn. The yuan-holder regains spent legendary actions at the start of its turn.

Eye Ray. The yuan-holder uses one random eye ray.