Dragon, Umbral (Ancient)

Gargantuan dragon, chaotic evil

Armor Class 22 (natural armor)
Hit Points 546 (28d20 + 252)
Speed 40 ft., climb 40 ft., fly 80 ft.

STR	DEX	CON	INT	WIS	CHA
30 (+10)	10 (+0)	29 (+9)	23 (+6)	24 (+7)	23 (+6)

Saving Throws Dexterity +7, Constitution +16, Wisdom +14, Charisma +13
Skills Perception +14, Stealth +14
Damage Resistances necrotic
Damage Immunities fire
Senses blindsight 60 ft., darkvision 120 ft., passive Perception 24
Languages Common, Draconic
Challenge 24 (62,000 XP)

Special Traits

• Legendary Resistance (3/day). If the dragon fails a saving throw, it can choose to succeed instead.
• Living Shadow. While in dim light or darkness, the dragon has resistance to damage that isn’t force, psychic or radiant.
• Shadow Stealth. While in dim light or darkness, the dragon can take the Hide action as a bonus action.
• Sunlight Sensitivity. While in sunlight, the dragon has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight.
• Innate Spellcasting. The dragon’s spellcasting ability is Charisma (spell save DC 21, +13 to hit with spell attacks). The dragon can innately cast the following spells at will, requiring no material components:
  • detect evil and good, darkness.

Actions

• Multiattack. The dragon can use its Frightful Presence and make three attacks: one with its bite and two with its claws.
• Bite. Melee Weapon Attack: +17 to hit, reach 15 ft., one target. Hit: 26 (3d10 + 10) piercing damage plus 14 (4d6) necrotic damage.
• Claws. Melee Weapon Attack: +17 to hit, reach 10 ft., one target. Hit: 23 (3d8 + 10) slashing damage.
• Tail. Melee Weapon Attack: +17 to hit, reach 15 ft., one target. Hit: 28 (4d8 + 10) 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 21 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.
• Shadow Breath (Recharge 5-6). The dragon exhales shadowy flames in a 90-foot cone. Each creature in the that area must make a DC 24 Dexterity saving throw, taking 91 (26d6) necrotic damage on a failed save, or half as much damage on a successful one. A humanoid reduced to 0 hit points by this damage dies, and an undead shadow rises from its corpse and acts immediately after the dragon in the initiative count. The shadow is under the dragon’s control.

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 25 Dexterity saving throw or take 24 (4d6 + 10) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.