Ancient Blue Dragolich

Before stands the epitome of undeath. Behold, your doom has arrived.

MultiattackThe dracolich can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws. Bite Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit:  (20d20) piercing damage plus  (20d20) lightning damage.

Claw Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: (20d20) slashing damage.

Tail Attack: +12 to hit, reach 15 ft., one target. Hit:(20d20) bludgeoning damage.

Frightful Presence Each creature of the dracolich's choice that is within 120 feet of the dracolich and aware of it must succeed on a DC 18 Wisdom saving throw or become frightened for 1 minute. 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 dracolich's Frightful Presence for the next 24 hours.

Lightning Breath (Recharge 5-6)The dracolich exhales lightning in a 90-foot line that is 5 feet wide. Each creature in that line must make a DC 20 Dexterity saving throw, taking (20d20) lightning damage on a failed save, or half as much damage on a successful one.

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

MagicResistance the dracolich has advantage on saving throws against spells and other magical effects.

DetectThe dracolich makes a Wisdom (Perception) check.

Tail Attack  the dracolich makes a tail attack.Wing Attack (Costs 2 Actions)The dracolich beats its tattered wings. Each creature within 10 ft. of the dracolich must succeed on a DC 21 Dexterity saving throw or take (20d20) bludgeoning damage and be knocked prone. After beating its wings this way, the dracolich can fly up to half its flying speed.