Ambush Hunter.

When the dragon burrows at least 15 feet straight toward a creature on the surface and then hits it with a melee attack on the same turn, the target takes an extra 7 (2d6) damage of the same type as the triggering attack. Any creature within 5 ft. of the dragon when it reaches the surface must succeed on a DC 15 Dexterity saving throw or be pushed 5 ft. away from the dragon in a straight line and knocked prone.

Drakhan Resistance.

The dragon has advantage on all saving throws against spells and spell-like abilities and is immune to the maze spell.

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

• Bite. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 13 (2d10 + 4) piercing damage.

• Claw. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) piercing damage plus 7 (2d6) slashing damage.

Breath Weapons (Recharge 5–6). The dragon uses one of the following:

• Dragonfire. The dragon breathes fire in a 30-foot cone. Each creature in the area must make a DC 16 Dexterity saving throw, taking 42 (12d6) fire damage on a failed save, or half as much on a success.

• Sandblast. The dragon spits a swirling ball of tiny gravel shards at a point it can see within 15 feet, where it detonates in an explosion of flame and shrapnel. Each creature in a 10-foot radius sphere centered on that point must make a DC 16 Dexterity saving throw. On a failed save, a creature takes 18 (4d8) fire damage and 18 (4d8) slashing damage and is blinded until the beginning of the dragon’s next turn. On a successful save, the creature takes half as much damage and is not blinded.

Sand Shroud.
When the dragon is hit with an attack, it can beat its wings, creating an obscuring dust cloud in a 10-foot radius around itself. Until the start of its next turn, the area is heavily obscured to creatures other than the dragon. Wind disperses the cloud.