Ancient War Shrike

Keen Sight. The roc has advantage on Wisdom (Perception) checks that rely on sight.

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

Innate Spellcasting. War shrikes Spellcasting ability modifier is Intelliegence (Spell save DC 22, +14 to hit with spell attacks). They can innately cast the following spells with no material components:

Cantrips: lightning lure, shocking grasp

3/day call lightning, lightning bolt

1/day: storm of vengeance

Multiattack. The shrike makes three attacks: two with its beak and one with its talons.

Beak. Melee Weapon Attack: +17 to hit, reach 15 ft., one target. Hit: 21 (3d8 + 9) piercing damage.

Talons. Melee Weapon Attack: +17 to hit, reach 5 ft., one target. Hit: 23 (4d6 + 9) slashing damage, and the target is grappled (escape DC 19). Until this grapple ends, the target is restrained, and the roc can't use its talons on another target.

Wings of the Storm. The Shrike Discharges lightning in a 15 foot radius from itself. Creatures within the Radius must make a DC 24 Dexterity Saving throw or take 60 (20d6) lightning damage.

Agonizing Stare. The Shrike focuses on 1 creature that it can see and can see it. The creature must make a DC 21 Wisdom saving throw. On a failure the creature takes 2d8 psychic damage and is frightened of the Shrike for 1 minute. The creature may repeat the saving throw at the end of each of its turns, on a failure the target remains afraid but takes no subsequent damage. On a success the fear effect ends.

Wings of Wind. The Shrike beats its wings. Each Creature within 30 ft. must succeed on a DC 25 strength saving throw or be knocked back 30 ft. and prone. The Shrike may then use its full movement.

Call the Flock. If the Shrike is within 1 mile of its territory it can emit a cry that will cause its Flock to come to its aid. The Flock is summoned at supernatural speed and will arrive on initiative count 20 of the next round. 1d10+5 War shrikes arrive to its aid.