Traits
Amphibious
The dragon can breathe air and water.Legendary Resistance (3/Day)
If the dragon fails a saving throw, it can choose to succeed instead.Actions
Multiattack
The dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.Bite
Melee Weapon Attack: to hit, reach 15 ft., one target. Hit:21 () piercing damage.Claw
Melee Weapon Attack: to hit, reach 10 ft., one target. Hit:17 () slashing damage.Tail
Melee Weapon Attack: to hit, reach 20 ft., one target. Hit:19 () 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 24 Wisdom saving throw or become 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.Breath Weapons (Recharge 5–6)
The dragon uses one of the following breath weapons.Change Shape
The dragon magically polymorphs into a humanoid or beast that has a challenge rating no higher than its own, or back into its true form. It reverts to its true form if it dies. Any equipment it is wearing or carrying is absorbed or borne by the new form (the dragon's choice).In a new form, the dragon retains its alignment, hit points, Hit Dice, ability to speak, proficiencies, Legendary Resistance, lair actions, and Intelligence, Wisdom, and Charisma scores, as well as this action. Its statistics and capabilities are otherwise replaced by those of the new form, except any class features or legendary actions of that form.Legendary Actions
Legendary Action Uses: 3. Immediately after another creature's turn, the Ancient Gold Dragon can expend a use to take one of the following actions. The Ancient Gold Dragon regains all expended uses at the start of each of its turns.
Detect
The dragon makes a Wisdom () check.Tail Attack
The dragon makes a tail attack.Wing Attack (Costs 2 Actions)
The dragon beats its wings. Each creature within 15 feet of the dragon must succeed on a DC 25 Dexterity saving throw or take 17 () bludgeoning damage and be knocked . The dragon can then fly up to half its flying speed.