Ancient Brown Dragon

If an adult brown dragon is able to eat its weight in food each day for 10,000 days, it will grow to become an ancient brown dragon. The gourmands of dragonkind, these massive creatures have an exquisite taste in food with an appetite to match. At this stage in life a brown dragon has sampled all confections it can find and knows what it wants. They have incredibly specific preferences that seem absurd to even the most refined of palates. An ancient brown dragon’s favorite food may be boiled chocolate mixed with gold and rubies or chilled elf brains in a watermelon bowl. These dishes are rarely things the dragons can get on their own, so they typically enlist a cooking staff to prepare their extensive meals. In the rare case these dragons encounter something they have not eaten, they pursue it with a hunger reminiscent of their youth. Given their impressive power at this age, nothing escapes an ancient brown dragon looking to try something new.


ANCIENT BROWN DRAGON

Gargantuan dragon, any evil alignment

Armor Class 23 (natural armor)
Hit Points 577 (33d20 + 231)
Speed 50 ft., burrow 50 ft., climb 50 ft., fly 60 ft.

STR DEX CON INT WIS CHA
30 (+10) 10 (+0) 25 (+7) 13 (+1) 20 (+5) 6 (-2)

Saving Throws Str +18, Dex +8, Con +15, Wis +13
Skills Athletics +26, Intimidation +14, Perception +13
Damage Resistances acid, cold, fire, lightning, poison
Senses darkvision 120 ft., tremorsense 120 ft., passive Perception 23
Languages Common, Draconic
Challenge 25 (75,000 XP)


TRAITS

Hyper Metabolism. When the dragon digests a flesh-and blood creature of Small size or larger, it regains 35 (10d6) hit points. A dead creature or a creature at 0 hit points that is swallowed by the dragon is immediately digested.
Juggernaut. If the dragon would be moved from its space, it may take a reaction to prevent that movement.
Legendary Resistance (3/Day). When the dragon fails a saving throw, it can choose to succeed instead.


ACTIONS

Multiattack. The dragon makes three attacks: one with its Bite or Munch, and two with its Claw.
Bite. Melee Weapon Attack: +18 to hit, reach 10 ft., one target. Hit: 49 (6d12 + 10) piercing damage. If the target is a creature, it is grappled and restrained (escape DC 26).
Challenging Roar. The dragon roars a mighty challenge to its enemies. Each creature within 120 feet that can hear the roar must succeed on a DC 26 Wisdom saving throw or be compelled to meet the dragon’s challenge for 1 minute. A creature so challenged cannot willingly move away from the dragon and cannot affect creatures other than the dragon with its spells, attacks, or abilities. A creature may repeat its saving throw at the end of each of its turns, ending the effect on a success. A creature immune to the charmed condition is immune to this effect.
Claw. Melee Weapon Attack: +18 to hit, reach 10 ft., one target. Hit: 32 (4d10 + 10) slashing damage.
Flensing Breath (Recharge 5–6). The dragon exhales a blast of air and sand that tears flesh from bone in a 40-foot line that is 5 feet wide. Each creature in that line must attempt a DC 26 Constitution saving throw or take 90 (20d8) slashing damage, or half as much on a success. A creature that fails the saving throw by 5 or more has its hit point maximum reduced by an equivalent amount. This effect lasts until it takes a short or long rest or receives magical healing from a spell of 8th level or higher.
Munch. Melee Weapon Attack: +18 to hit, reach 5 ft., one Large or smaller creature grappled by the dragon. Hit: The creature is swallowed by the dragon. A swallowed creature is blinded and restrained, it has total cover against attacks and other effects outside the dragon, and it takes 28 (8d6) acid damage and 28 (8d6) bludgeoning damage at the start of each of the dragon’s turns. A creature with 0 hit points that takes this damage is digested.
If the dragon takes 40 damage or more on a single turn from a creature inside it, the dragon must succeed on a DC 25 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, which fall prone in a space within 10 feet of the dragon. If the dragon dies, a swallowed creature is no longer restrained by it and can escape from the corpse by using 20 feet of movement, exiting prone.


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.
Claw. The dragon makes a Claw attack.
Dash. The dragon moves up to its speed.
Flex. The dragon attempts a Strength (Athletics) check that it could attempt as an action.
Munch (Costs 2 Actions). The dragon makes a Munch attack.


Ref: TPKB1 p79