Earth Flight. As part of a Cobalt Dragon's movement, it may enter the ground and move through it as if flying.

Legendary Resistance (3/Day). If the dragon fails a saving throw, it can choose to succeed instead.

Multiattack. The dragon makes one Bite attack and two Claw attacks.

Bite. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 14 (2d10+3) piercing damage. On a hit, the target creature must make a STR Saving Throw (DC 18) or be caught in a sap and restrained. The saving throw can be repeated on subsequent turns, but if the sap is not escaped within 3 turns, it crystallizes and the DC increases to 21.

Claw. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 8 (1d8+3) slashing damage.

Earth Breath (2/Short Rest). The dragon spews a 20 ft. line of telekinetically controlled sap onto an unoccupied area, and can lift the earth in a 10 ft. sphere. As a bonus action as part of the creation and on subsequent turns, the dragon may use the earth to perform a Slam Attack. The Earth Breath must be concentrated on as if concentrating on a spell. While maintaining this sphere, the dragon cannot speak and cannot perform actions or spells that require speaking.

Spellcasting (Earth Magic). The dragon casts one of the following spells, requiring no spell components and using Wisdom as the spellcasting ability (spell save DC 22). To cast them the dragon must be standing on earth or stone. Each spell is cast at its lowest level.

2/day each: earth tremor, spike growth, erupting earth, wall of stone, earthquake

Change Shape. The dragon magically transforms into any creature that is Medium or Small, while retaining its game statistics (other than its size). This transformation ends if the dragon is reduced to 0 hit points or uses a bonus action to end it.

Earthen Tomb (2/Long Rest). The dragon can create a cocoon of Earth around itself, and heals by 4 hit dice at the end of every turn it remains inside said cocoon. The dragon cannot take any actions, bonus actions, or reactions inside the cocoon and has a movement speed of 0, but maintains awareness of surroundings via its Tremorsense. The cocoon has an AC of 14, and a health pool of 1/2 (rounding up when necessary) the dragon's HP when summoned.

Slam Attack. Melee Spell Attack  DC 22, reach 20 ft., 10 ft. sphere. After using its Breath Weapon, the Amber Dragon may slam the 10 ft. sphere of earth at a point centered within the 20 ft. range of its sap. On a failed DEX saving throw the target takes (2d8+6) bludgeoning damage, and has movement reduced by 10 ft until the end of its next turn.

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 one claw attack.

Earth Magic (Costs 2 Actions). The dragon uses Earthen Tomb or Spellcasting.