Sphinx

Sphinxes are a race of intelligent, immortal magical beasts. A sphinx guards in sacred isolation the secrets and treasures of the gods. Its great wings sweep along its flanks, its tawny leonine body rippling with muscle and possessed of forepaws powerful enough to tear a humanoid in half.

Androsphinx
An androsphinx bears the head of a humanoid male on its lion's body. Outwardly gruff and downcast, it often begins conversations with insults or negative observations. Beneath this gruff exterior, however, an androsphinx has a noble heart. It has no wish to lie or deceive, but it doesn't give away information readily, choosing its words as wisely as it guards its secrets.

Gynosphinx
A gynosphinx bears the head of a humanoid female. Many have the regal countenances of worldly queens, but some are marked with wild, leonine features. A gynosphinx's eyes see beyond the present time and place, and penetrate veils of invisibility and magic. Supplicants who look deep into those eyes might find themselves magically displaced, banished to some far-flung plane where a difficult trial awaits them.

Abilities
Both androsphinxes and gynosphinxes have the following abilities:
 * Damage Immunities: Psychic
 * Condition Immunities: Charmed, frightened
 * Senses: Truesight
 * Languages: Common and Sphinx
 * Inscrutable: The sphinx is immune to any effect that would sense its emotions or read its thoughts, as well as any divination spell that it refuses.
 * Multiattack: The sphinx can make two Claw attacks.
 * Legendary Actions: Claw attack, Teleport (120 feet), or Cast a Spell
 * Lair Actions

Androsphinx
In addition, androsphinxes also have the following abilities:
 * Damage Immunities: bludgeoning, piercing, and slashing from non magical weapons.
 * Roar: Three progressively louder roars, with various effects
 * Spellcasting: Androsphinxes can cast the following cleric spells:
 * Cantrips: sacred flame, spare the dying, thaumaturgy
 * 1st level: command, detect evil and good, detect magic
 * 2nd level: lesser restoration, zone of truth
 * 3rd level: dispel magic, tongues
 * 4th level: banishment, freedom of movement
 * 5th level: flame strike, greater restoration
 * 6th level: heroes' feast

Gynosphinx
In addition to the abilities shared with androsphinxes, gynosphinxes have the following abilities:
 * Damage Resistances:Bludgeoning, piercing, and slashing from non magical weapons
 * Spellcasting: Gynosphinxes can cast the following wizard spells:
 * Cantrips: mage hand, minor illusion, prestidigitation
 * 1st level: detect magic, identify, shield
 * 2nd level: darkness, locate object, suggestion
 * 3rd level: dispel magic, remove curse, tongues
 * 4th level: banishment, greater invisibility
 * 5th level: legend lore

Known Sphinxes

 * Osysa - a gynosphinx residing beneath the guildhall of the Slayer's Take, and the keeper of the temple to Ioun in Vasselheim.
 * Kamaljiori - androsphinx mate of Osysa. Vox Machina sought him out and, upon passing his trial, Kamaljiori gifted them one of the Vestiges, Mythcarver, and revealed the names and locations of some other Vestiges.
 * Yondis the Winter Star - androsphinx in the Flotket Alps. He watches over the tomb of a heroic group of champions who sacrificed themselves in the final battles of the Calamity. Those who prove their worth may earn the right to use the heroes' relics.