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

Bite. Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit: 17 (2d10 + 6) piercing damage plus 11 (2d10) poison damage.

Claw. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 13 (2d6 + 6) slashing damage.

Tail. Melee Weapon Attack: +12 to hit, reach 15 ft., one target. Hit: 10 (1d8 + 6) bludgeoning damage. If the target is a creature, it must succeed on a DC 20 Strength saving throw or be knocked prone.

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 its action to end it.

Nightmare Breath (Recharge 5–6). The dragon exhales a cloud of spores in a 90-foot cone. Each creature in that area must make a DC 19 Wisdom saving throw. On a failed save, the creature takes 49 (9d10) psychic damage, and it is frightened of the dragon for 1 minute. On a successful save, the creature takes half as much damage with no additional effects. A frightened creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Commanding Spores. The dragon releases spores around a creature within 30 feet of it that it can see. The target must succeed on a DC 19 Wisdom saving throw or use its reaction to make a melee weapon attack against a random creature within reach. If no creatures are within reach, or the target can't take a reaction, it takes 11 (2d10) psychic damage.

Tail. The dragon makes one Tail attack.

Spore Salvo (Costs 2 Actions). The dragon releases poisonous spores around a creature within 30 feet of it that it can see. The target must succeed on a DC 19 Constitution saving throw or take 28 (8d6) poison damage and become poisoned for 1 minute. The poisoned creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.