Adult Gold Dragon

Traits

Amphibious

The dragon can breathe air and water.

Legendary Resistance (3/Day, or 4/Day in Lair)

If the dragon fails a saving throw, it can choose to succeed instead.

Actions

Multiattack

The dragon makes three Rend attacks. It can replace one attack with a use of (A) Spellcasting to cast Guiding Bolt (level 2 version) or (B) Weakening Breath.

Rend

Melee Attack: +14, reach 10 ft. Hit: 17 (2d8 + 8) Slashing damage plus 4 (1d8) Fire damage.

Fire Breath (Recharge 5–6)

Dexterity Saving Throw: DC 21, each creature in a 60-foot Cone. Failure: 66 (12d10) Fire damage. Success: Half damage.

Weakening Breath

Strength Saving Throw: DC 21, each creature that isn't currently affected by this breath in a 60-foot Cone. Failure: The target has Disadvantage on Strength-based D20 Tests and subtracts 3 (1d6) from its damage rolls. It repeats the save at the end of each of its turns, ending the effect on itself on a success. After 1 minute, it succeeds automatically.

Legendary action uses: 3 (4 in its lair). The creature can use one option at the end of another creature’s turn and regains spent uses at the start of its turn.

Legendary actions

Banish

Charisma Saving Throw: DC 21, one creature the dragon can see within 120 feet. Failure: 10 (3d6) Force damage, and the target has the Incapacitated condition and is transported to a harmless demiplane until the start of the dragon's next turn, at which point it reappears in an unoccupied space of the dragon's choice within 120 feet of the dragon. Success or Failure: The dragon can't take this action again until the start of its next turn.

Guiding Light

The dragon uses Spellcasting to cast Guiding Bolt (level 2 version).

Pounce

The dragon moves up to half its Speed, and it makes one Rend attack.

Spellcasting

The dragon casts one of the following spells, requiring no Material components and using Charisma as the spellcasting ability (spell save DC 21, +13 to hit with spell attacks):

At will: Detect Magic, Guiding Bolt (level 2 version), Shapechange (Beast or Humanoid form only, no Temporary Hit Points gained from the spell, and no Concentration or Temporary Hit Points required to maintain the spell)

1/day each: Flame Strike, Zone of Truth

Regional effects

The region containing an adult or ancient gold dragon's lair is altered by its presence, creating the following effects:

• Dream Messenger: While in its lair, the dragon can cast Dream, requiring no Material components and using Charisma as the spellcasting ability. When casting the spell this way, the dragon can target any creature within 6 miles.
• Foretelling Fog: The area within 1 mile of the lair is Lightly Obscured by opalescent fog. While in that area, creatures can't be surprised, as the fog swirls into shapes that warn of danger.

If the dragon dies or moves its lair elsewhere, these effects end immediately.