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

Abyssal Enigma. Zephyron's presence cloaks all magical auras within 30 ft., preventing magical detection and identification unless a successful DC 20 Intelligence (Arcana) check is made.

Dimensional Step. At the start of its turn, Zephyron can choose to become incorporeal. While incorporeal, it can move through other creatures and objects as if they were difficult terrain. It takes 5 (1d10) force damage if it ends its turn inside an object.

Spellcasting. Zephyron's innate spellcasting ability is Charisma (spell save DC 22). It can cast the following spells:

Multiattack. Zephyron makes two attacks: one with its Soul Tendril and one with its Mindrend Gaze.

Soul Tendril. Melee Weapon Attack: +14 to hit, reach 15 ft., one target. Hit: 32 (4d10 + 10) psychic damage, and the target must succeed on a DC 22 Wisdom saving throw or be frightened until the end of their next turn.

Mindrend Gaze. Ranged Spell Attack: +13 to hit, range 60 ft., one target. Hit: 40 (8d6 + 12) psychic damage and the target must succeed on a DC 22 Wisdom saving throw or be stunned until the end of Zephyron's next turn.

Reaping Transposition. Zephyron swaps places with any creature within 100 ft. as a bonus action. The target then takes 15 necrotic damage.

Zephyron can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Zephyron regains spent legendary actions at the start of its turn.

Ethereal Whispers. Zephyron makes a perception or insight check.

Grip of Despair. Zephyron attempts a Soul Tendril attack.