Huge dragon, chaotic evil

Armor Class: 18 (natural armour)

Hit Points: 256 (19d12+133) 19d12+133

Speed: 40 ft , fly: 80 ft , climb: 40 ft

STR

27 +8

DEX

10 +0

CON

25 +7

INT

16 +3

WIS

13 +1

CHA

21 +5

Saving Throws: Dexterity +6, Constitution +13, Wisdom +7, Charisma +11

Skills: Perception +13, Insight +4, Stealth +6

Damage Resistances: Bludgeoning, Piercing and Slashing from non-magical attacks

Damage Immunities: Fire

Condition Immunities: Frightened, charmed, exhaustion

Senses: Blindsight 60 ft., Darkvision 120 ft., Passive Perception 23

Languages: Draconic, Common

Challenge Rating: 17

Proficiency Bonus: +6

Actions

Multiattack. The dragon can use its Frightful Presence. It then makes up to three attacks: one with its bite and two with its claws/tail.   Bite (Ground only). Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 17 (2d10 + 8) piercing damage.   Claw (Flight only). Melee Weapon Attack: +14 to hit, reach 5 ft., one target. Hit: 17 (2d8 + 8) slashing damage.   Tail. Melee Weapon Attack: +14 to hit, reach 15 ft., one target. Hit: 13 (2d6 + 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 (Recharge 5–6). The dragon exhales fire in a 30-foot cone. Each creature in that area must make a DC 19 Dexterity saving throw, taking 56 (16d6) fire damage on a failed save, or half as much damage on a successful one.

Legendary Actions

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.   Wing Attack (Costs 2 Actions). The dragon beats its wings. Each creature within 10 feet of the dragon must succeed on a DC 19 Dexterity saving throw or take 15 (2d4 + 8) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.