{Generate a DND 5e Monster :b'Dragon, Brass (Ancient) \n'b'  Family:   Dragons - Metallic  \n'b'  Gargantuan   dragon ,  chaotic good  \n'b'  Armor Class  20 (natural armor)  Hit Points  297 (17d20 + 119)  Speed  40 ft., burrow 40 ft., fly 80 ft.\n'b' STATS STR: 27 (+8) DEX:  10 (+0)  CON:  25 (+7)  INT:  16 (+3)  WIS:  15 (+2)  CHA:  19 (+4)  \n'b'\n'b'\n'b'\n'b'\n'b'\n'b'     Saving Throws   Dex  +6,  Con  +13,  Wis  +8,  Cha  +10  Skills   History  +9,  Perception  +14,  Persuasion  +10,  Stealth  +6  Damage Immunities  fire  Senses   blindsight  60 ft., darkvision 120 ft., passive Perception 24  Languages  Common, Draconic  Challenge  20 (25,000 XP) \n'b' Special Traits \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. It then makes three attacks: one with its bite and two with its claws. \n'b'  Bite :  Melee Weapon Attack : +14 to hit, reach 15 ft., one target.  Hit : 19 (2d10 + 8) piercing damage. \n'b'  Claw :  Melee Weapon Attack : +14 to hit, reach 10 ft., one target.  Hit : 15 (2d6 + 8) slashing damage. \n'b'  Tail :  Melee Weapon Attack : +14 to hit, reach 20 ft., one target.  Hit : 17 (2d8 + 8) 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 18  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'  Breath Weapons (Recharge 5-6) : The dragon uses one of the following breath weapons: \n'b'   Fire Breath : The dragon exhales fire in an 90-foot line that is 10 feet wide. Each creature in that line must make a DC 21  Dexterity  saving throw, taking 56 (16d6) fire damage on a failed save, or half as much damage on a successful one. \n'b'  Sleep Breath : The dragon exhales sleep gas in a 90-foot cone. Each creature in that area must succeed on a DC 21  Constitution  saving throw or fall unconscious for 10 minutes. This effect ends for a creature if the creature takes damage or someone uses an action to wake it. \n'b'   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\xe2\x80\x99s 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. \n'b'\n'b'     Legendary Actions \n'b'\n'b' 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\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'  Wing Attack (Costs 2 Actions) : The dragon beats its wings. Each creature within 15 feet of the dragon must succeed on a DC 22  Dexterity  saving throw or take 15 (2d6 + 8) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed. \n'b'  About \n'b' A crest of horns sweeps back from the head of this dragon, leading to a long neck and serpentine brass body.'}