Adult King Tyrant

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

Multiattack. The dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its tail, each attack must be against a different creature.

Bite. Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 38 (5d10 + 8) piercing damage plus 12 (3d6) fire damage.

Tail. Melee Weapon Attack: +14 to hit, reach 15 ft., one target. Hit: 38 (6d8 + 8) bludgeoning damage.

Frightful 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 19 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 dragon's Frightful Presence for the next 24 hours.

Fire Breath. The Tyrant exhales fire in a 60-foot line/cone. Each creature in that area must make a DC 21 Dexterity saving throw, taking 63 (18d6) fire damage on a failed save, or half as much damage on a successful one. Recharges after 3 rounds.

The dragon 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 dragon regains spent legendary actions at the start of its turn.

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

Tail Attack. The dragon makes a tail attack.

Charge (costs 2). The Tyrant charges forward 60ft trampleing any creatures that is large or smaller in it's path, cratures that are trampled must make a DC 19 Str save, taking 24 (2d12+10) bludgeoning damage on a failed save and getting knocked prone, on a successful save the creature take half damage and isn't knocked prone.