Great Wyrm Black Dragon (5e Creature)
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Great Wyrm Black Dragon
Titanic dragon, chaotic evil
Saving Throws Dex +11, Con +18, Wis +13, Cha +16
Amphibious. The dragon can breathe air and water.
Acid Absorption. Whenever the dragon is subjected to acid damage, it takes no damage and instead regains a number of hit points equal to the acid damage dealt.
Acid Blood. The dragon's blood not red but a vibrant yellow-green and just toxic as its saliva. Whenever the dragon suffers slashing or piercing damage from a melee attack, if the attacker is within 5 feet of the dragon, they suffer 14 (3d8) acid damage. The dragon is immune to the Contagion spell and to all effects that would cause disease.
Dissolving acid. When a character wearing nonmagical armor suffers damage from the dragon's acid breath, their armor is destroyed. When a character wielding a nonmagical weapon suffers damage from the dragons Acid Blood, their weapon is destroyed.
Legendary Resistances (5/Day). If the dragon fails a saving throw, it can choose to succeed instead.
Magic Resistance. The dragon has an advantage on saving throws against spells and other magical effects.
Massive Jaws. The dragon has huge, strong jaws like a massive crocodile. It deals +20 piercing damage with successful bite attacks.
Mythic Acid. The incredible power of this creature's acid is more powerful than the strongest enchantments. Characters who are normally immune to acid damage instead are treated as if they are resistant to the acid damage caused by this dragon and characters who are resistant to lightning damage instead treat it as if they were not. Characters who are not resistant to acid damage are treated as if they were vulnerable to the acid damage of this dragon.
Siege Monster. The dragon deals double damage to objects and structures.
Stone dissolve. When the dragon uses its breath weapon on a stone structure, it can make a DC 20 Constitution check. On a success, the structure dissolves away and turns into a bubbling pool of acid which releases toxic fumes into the air, dealing 18 (5d6) poison damage and 32 (7d8) acid damage to all characters who enter it and to all characters begin their turn in it. On a failure, the structure suffers 180 (20d8x2) acid damage. If the structure is destroyed by this, it will collapse into rubble.
Toxic Aura. When a hostile character begins its turn within 30 feet of the dragon, they have to make a Constitution save vs 19 or suffer 1 point of Exhaustion.
Multiattack. The dragon can use its Frightful Presence. It then makes six attacks: one with its bite, four with its claws, and one with its tail sweep.
Bite. Melee Weapon Attack: +19 to hit, reach 15 ft., one target. Hit: 52 (4d10 + 30) piercing damage plus 13 (2d12) acid damage and DC 20 Strength Saving throw or be swallowed. At the start of each turn, all swallowed characters suffer 23 (5d8) bludgeoning + 32 (7d8) acid damage and are considered restrained and asphyxiating. It requires 70 internal damage in a single round for the Dragon to make a Constitution save vs DC 25. On failure, it vomits up all swallowed characters, releasing them and dealing half its normal acid breath damage to all characters in a 100-foot line, with a successful DC 26 Dexterity saving throw negating all damage. If a character is reduced to 0 HP while swallowed by the dragon, their body is dissolved.
Claw. Melee Weapon Attack: +19 to hit, reach 10 ft., one target. Hit: 24 (4d6 + 10) slashing damage.
Tail sweep. Melee Weapon Attack: +15 to hit, reach 20 ft., up to 5 targets within range. Hit: 17 (2d6 + 10) bludgeoning damage.
Mythic Frightful Presence. Each creature of the dragon's choice that is within 240 feet of the dragon and aware of it must succeed on a DC 26 Wisdom saving throw or become frightened for 1 minute. A creature that is frightened is also paralyzed. A creature of CR 10 or lower who becomes frightened in this way suffers a heart attack, instantly dropping to 0 HP and falling unconscious. A creature that would be made immune to fear through magic instead receives an advantage on its saving throw. 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.
Mythic reactions. The dragon can make six reactions each round, one with its bite attack, four with its claw attacks, and one with its tail.
Tail. Melee Weapon Attack: +19 to hit, reach 20 ft., one target. Hit: 28 (4d8 + 10) bludgeoning damage + if target is Huge or smaller, they are knocked prone.
The dragon can take 5 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.
Caustic Gaze (Costs 2 actions, 1/Day). The dragon chooses a character with 60 feet. That character loses 2d6 Constitution points. If this would lower a character to 0 Constitution, their blood turns to acid for the next 1 minute and if they are not immune to acid, they fall dead. Otherwise, they become incapacitated for 1d4 rounds.