b'Dragon, Dust (Ancient) \n'b'  Gargantuan   dragon ,  neutral evil  \n'b'  Armor Class  22 (natural armor)  Hit Points  487 (25d20 + 225)  Speed  40 ft., burrow 30 ft., fly 80 ft.\n'b' STATS STR: 30 (+10) DEX:  10 (+0)  CON:  29 (+9)  INT:  18 (+4)  WIS:  15 (+2)  CHA:  23 (+6)  \n'b'\n'b'\n'b'\n'b'\n'b'\n'b'     Saving Throws   Dexterity  +7,  Constitution  +16,  Wisdom  +9,  Charisma  +13  Skills   Perception  +16,  Stealth  +7  Damage Immunities  acid  Senses   blindsight  60 ft.,  darkvision  120 ft., tremorsense 60 ft., passive  Perception  26  Languages  Common, Draconic, Terran  Challenge  23 (50,000 XP) \n'b' Special Traits \n'b'   Innate Spellcasting . The ancient dust dragon\xe2\x80\x99s innate spellcasting ability is  Constitution  (spell save DC 24). It can cast the following spells, requiring no material components. \n'b'   3/day :  create or destroy water  (destroy only) \n'b'  2/day :  stone shape  \n'b'  1/day :  wall of stone  \n'b'   Earthglide . The dragon can burrow through nonmagical, unworked earth and stone. While doing so, the dragon doesn\xe2\x80\x99t disturb the material it moves through. \n'b'  Legendary Resistance  (3/day). If the dragon fails a saving throw, it can choose to succeed instead. \n'b'  Actions \n'b'   Multiattack . The dragon can use its Frightful Presence and make one Bite  attack  and two Claw attacks. \n'b'  Bite .  Melee Weapon Attack : +17 to hit, reach 15 ft., one target.  Hit : 21 (2d10 + 10) piercing damage plus 14 (4d6) acid damage. \n'b'  Claw .  Melee Weapon Attack : +17 to hit, reach 10 ft., one target.  Hit : 17 (2d6 + 10) slashing damage. \n'b'  Tail .  Melee Weapon Attack : +17 to hit, reach 20 ft., one target.  Hit : 19 (2d8 + 10) bludgeoning damage. \n'b'  Frightful Presence . Each creature of the dragon\xe2\x80\x99s choice that is within 120 feet of the dragon and aware of it must succeed on a DC 21  Wisdom  saving throw or become  frightened  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\xe2\x80\x99s saving throw is successful or the effect ends for it, the creature is immune to the dragon\xe2\x80\x99s Frightful Presence for the next 24 hours. \n'b'  Sand Breath  (recharge 5-6). The dragon exhales shards of stone and dust in a 90-foot cone. Each creature in that area must succeed on a DC 24  Dexterity  saving throw, taking 85 (19d8) slashing damage on a failed saving throw, or half as much damage on a successful one. \n'b'  Legendary Actions \n'b' The dragon can take 3 legendary  actions , choosing from the options below. Only one legendary action can be used as a time and only at the end of another creature\xe2\x80\x99s turn. The dragon regains spent legendary  actions  at the start of its turn. \n'b'   Detect . The dragon makes a  Wisdom  ( Perception ) check. \n'b'  Tail Attack . The dragon makes a Tail  attack . \n'b'  Sandstorm  (costs 2  actions ). The ancient dust dragon creates a swirling maelstrom of sand and dust in a 120-foot radius centered on itself, which swirls until the end of the ancient dust dragon\xe2\x80\x99s next turn. Creatures in the area must succeed on a DC 26  Constitution  saving throw or be  blinded  for 1 minute. Creatures can repeat the saving throw at the end of each of its turns, ending the effect on a success. The ancient dust dragon is immune to the effects of its Sandstorm. \n'b'  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 (2d6 + 10) bludgeoning damage and be knocked  prone . The dragon can then  fly  up to half its flying speed. \n'b'  Lair Actions \n'b' On  initiative  count 20 (losing  initiative  ties), the dragon takes a lair action to cause one of the following effects; the dragon can\xe2\x80\x99t use the same effect two rounds in a row: \n'b'  The solid stone surrounding a point on the ground that the dragon can see within 120 feet of it turns into dust and sand in a 20-foot radius. The area is considered  difficult terrain , and if a creature enters or begins their turn in the area it must make a DC 18  Strength  saving throw or become  restrained  by the sudden quicksand. A  restrained  creature can use its action to attempt to free itself by making a DC 18  Strength  check. \n'b' The dust dragon chooses one creature it can see within 60 feet of it to begin to petrify, as if the dust dragon had cast the  flesh to stone  spell. The DC for this effect is 22. \n'b' The dust dragon creates a column of swirling sand that is 10 feet in diameter and 40 feet high that continues churning until the start of the next  initiative  count 20. Creatures that enter or begin their turn in the area must make a DC 18  Dexterity  saving throw, taking 17 (5d6) slashing damage on a failed saving throw, or half as much damage on a successful one. \n'b'  Regional Effects \n'b' The region containing a legendary dust dragon\xe2\x80\x99s lair is warped by the dragon\xe2\x80\x99s presence, which creates one or more of the following effects: \n'b'  Creatures who succumb to the environment within 6 miles of the dust dragon\xe2\x80\x99s lair often rise as dust ghouls under the dust dragon\xe2\x80\x99s  command . \n'b' Oasis and water sources within 1 mile of the lair dry up and become sand and dust quickly. \n'b' Dust mephits and other similar creatures find themselves at home within the area, and often  attack  intruders on sight.'