Ancient Copper Dracolich

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

Magic Resistance. The dracolich has advantage on saving throws against spells and other magical effects.

Multiattack. The dracolich can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.

Bite. Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 19 (2d10 + 8) piercing damage.

Claw. Melee Weapon Attack: +16 to hit, reach 10 ft., one target. Hit: 15 (2d6 + 8) slashing damage.

Tail. Melee Weapon Attack: +16 to hit, reach 20 ft., one target. Hit: 17 (2d8 + 8) 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 20 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.

Breath Weapons (Recharge 5–6). The dracolich uses one of the following breath weapons.

Acid Breath. The dracolich exhales acid in an 90-foot line that is 10 feet wide. Each creature in that line must make a DC 23 Dexterity saving throw, taking 63 (14d8) acid damage on a failed save, or half as much damage on a successful one.

Slowing Breath. The dracolich exhales gas in a 90-foot cone. Each creature in that area must succeed on a DC 23 Constitution saving throw. On a failed save, the creature can't use reactions, its speed is halved, and it can't make more than one attack on its turn. In addition, the creature can use either an action or a bonus action on its turn, but not both. These effects last for 1 minute. The creature can repeat the saving throw at the end of each of its turns, ending the effect on itself with a successful save.

Change Shape. The dracolich magically polymorphs into a humanoid or beast that has a challenge rating no higher than its own, or back into its true form. It reverts to its true form if it dies. Any equipment it is wearing or carrying is absorbed or borne by the new form (the dracolich's choice).

In a new form, the dracolich retains its alignment, hit points, Hit Dice, ability to speak, proficiencies, Legendary Resistance, lair actions, and Intelligence, Wisdom, and Charisma scores, as well as this action. Its statistics and capabilities are otherwise replaced by those of the new form, except any class features or legendary actions of that form.

The dracolich can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The dracolich regains spent legendary actions at the start of its turn.

Detect. The dracolich makes a Wisdom (Perception) check.

Tail Attack. The dracolich makes a tail attack.

Wing Attack (Costs 2 Actions). The dracolich beats its wings. Each creature within 15 feet of the dracolich must succeed on a DC 24 Dexterity saving throw or take 15 (2d6 + 8) bludgeoning damage and be knocked prone. The dracolich can then fly up to half its flying speed.