Multiattack

The ouroboros can use its Introspective Presence. It then makes two bite attacks.

Bite

Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 10 (1d10 + 5) piercing damage.

Introspective Presence

Each creature of the dragon's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 15 Wisdom saving throw or be incapacitated for 1 minute as the creature is overcome by introspective thoughts. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the dragon's Introspective Presence for the next 24 hours.

Kaleidoscopic Breath (Recharge 5-6)

The ouroboros exhales energy in a 30-foot cone. Each creature in that area must make a DC 15 Dexterity saving throw, taking 27 (6d8) damage on a failed save, or half as much damage on a successful one. The damage is either acid, cold, fire, lightning, necrotic, poison, radiant, or thunder. The dragon chooses the type of damage before exhaling.