Actions

Multiattack. The dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.   Bite. Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: (2d10 + 2) piercing damage.   Claw. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: (2d6 + 2) slashing damage.   Tail. Melee Weapon Attack: +8 to hit, reach 15 ft., one target. Hit: (2d8 + 2) bludgeoning damage.   Frightening Presence. Each creature of the dragon's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 23 (8 + Prof + Cha) 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's saving throw is successful or the effect ends for it, the creature is immune to the dragon's Frightful Presence for the next 24 hours.   Acid Breath (Recharge 5-6). The dragon exhales acid in an 60-foot line that is 5 feet wide. Each creature in that line must make a DC 21 (8 + Prof + Dex) Dexterity saving throw, taking 77 (17d8) acid damage on a failed save, or half as much damage on a successful one.   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's 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.   Forced Hostility (Recharge 6). The dragon forces one target it can see within 120ft of it to make a DC 23 (8 + Prof + Cha) wisdom saving throw, on a failure the target has illusory layer over all of it's senses, besides touch, making every other creature seem like a hostile draconic copper versions of them selves, these illusions cannot deal damage and does not interfere with any of the target's attempts to hit the creature, the target can repeat this save at the end of each of it's turns ending the effect on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the dragon's Forced Hostility for the next 24 hours.

Legendary Actions

Adult Copper 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. Adult Copper Dragon regains spent legendary actions at the start of their turn.   Detect. The dragon makes a Wisdom (Perception) check.   Tail Attack. The dragon makes a tail attack.   Produce Shimmer. The dragon creates a duplicate from it's Shimmer Form feature.   Wing Attack (Costs 2 Actions). The dragon beats its wings. Each creature within 10 ft. of the dragon must succeed on a DC 16 (8 + Prof + Str) Dexterity saving throw or take 11 (2d6 + 2) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.

Lair Actions

On initiative count 20 (losing initiative ties), the dragon takes a lair action to cause one of the following effects:  

• The dragon chooses a point on the ground that it can see within 120 feet of it. Stone spikes sprout from the ground in a 20-foot radius centered on that point. The effect is otherwise identical to the spike growth spell and lasts until the dragon uses this lair action again or until the dragon dies.
• The dragon chooses a 10-foot-square area on the ground that it can see within 120 feet of it. The ground in that area turns into 3-foot-deep mud. Each creature on the ground in that area when the mud appears must succeed on a DC 15 Dexterity saving throw or sink into the mud and become restrained. A creature can take an action to attempt a DC 15 Strength check, freeing itself or another creature within its reach and ending the restrained condition on a success. Moving 1 foot in the mud costs 2 feet of movement. On initiative count 20 on the next round, the mud hardens, and the Strength DC to work free increases to 20.

Copper dragons dwell in dry uplands and on hilltops, where they make their lairs in narrow caves. False walls in the lair hide secret antechambers where the dragon stores valuable ores, art objects, and other oddities it has collected over its lifetime. Worthless items are put on display in open caves to tantalize treasure seekers and distract them from where the real treasure is hidden.

Regional Effects

The region containing a legendary copper dragon’s lair is warped by the dragon’s magic, which creates one or more of the following effects:  

• Magic carvings of the dragon’s smiling visage can be seen worked into stone terrain and objects within 6 miles of the dragon’s lair.
• Tiny beasts such as rodents and birds that are normally unable to speak gain the magical ability to speak and understand Draconic while within 1 mile of the dragon’s lair. These creatures speak well of the dragon, but can’t divulge its whereabouts.
• Intelligent creatures within 1 mile of the dragon’s lair are prone to fits of giggling. Even serious matters suddenly seem amusing.