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. Wisdom (Insight) checks made to ascertain the sphinx's intentions or sincerity have disadvantage.

Actions

Multiattack. The sphinx makes two Scythe attacks

Scyhte. Melee Weapon Attack: +12 to hit, reach 5ft., one target. Hit 17 (2d10 + 6) slashing damage

Roar (3/Day). The sphinx emits a magical roar. Each time it roars before finishing a long rest, the roar is louder and the effect is different, as detailed below. Each creature within 500 feet of the sphinx and able to hear the roar must make a saving throw

First Roar. Each creature that fails a DC 18 Wisdom saving throw is frightened for 1 minute. A frightened creature can repeat the saving throw at the end of each of its turn s, endin g the effect on itself on a success.

Second Roar. Each creature that fails a DC 18 Wisdom saving throw is deafened and frightened fo r 1 minute. A frightened creature is paralyzed and can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Third Roar. Each creature makes a DC 18 Constitution saving throw. On a failed save, a creature takes 44 (8d10) thund er damage and is knocked prone . On a successful save, the creature takes half as much damage and isn 't knocked prone.