Black Pudding Dragon (Adult)

Amphibious. The dragon can breathe air and water.

Amorphous. The pudding can move through a space as narrow as 1 inch wide without squeezing.

Corrosive Form. A creature that touches the black pudding dragon or hits it with a melee attack while within 5 feet of it takes 4 (1d8) acid damage. Any nonmagical weapon made of metal or wood that hits the black pudding dragon corrodes. After dealing damage, the weapon takes a permanent and cumulative -1 penalty to damage rolls. If its penalty drops to -5, the weapon is destroyed. Nonmagical ammunition made of metal or wood that hits the black pudding dragon is destroyed after dealing damage. The black pudding dragon can eat through 2-inch-thick, nonmagical wood or metal in 1 round.

Spider Climb. The black pudding dragon can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Legendary Resistance (3/Day). If the black pudding dragon fails a saving throw, it can choose to succeed instead.

Multiattack. The black pudding dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.

Bite. Melee Weapon Attack: +11 to hit, reach 10 ft., one target. Hit: (2d10 + 6) piercing damage plus (5d8)acid damage. In addition, nonmagical armor worn by the target is partly dissolved and takes a permanent and cumulative -1 penalty to the AC it offers. The armor is destroyed if the penalty reduces its AC to 10.

Claw. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: (2d6 + 6) slashing damage plus (4d8)acid damage. In addition, nonmagical armor worn by the target is partly dissolved and takes a permanent and cumulative -1 penalty to the AC it offers. The armor is destroyed if the penalty reduces its AC to 10.

Tail. Melee Weapon Attack: +11 to hit, reach 15 ft., one target. Hit: (2d8 + 6) bludgeoning damage plus (4d8)acid damage. In addition, nonmagical armor worn by the target is partly dissolved and takes a permanent and cumulative -1 penalty to the AC it offers. The armor is destroyed if the penalty reduces its AC to 10.

Acid Breath (Recharge 5-6). The black pudding dragon exhales acid in a 60-foot line that is 5 feet wide. Each creature in that line must make a DC 18 Dexterity saving throw, taking 54 (12d8) acid damage on a failed save, or half as much damage on a successful one.

Frightful Presence. Each creature of the black pudding dragon's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 16 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 black pudding dragon's Frightful Presence for the next 24 hours.

Split. When a black pudding dragon that is Medium or larger is subjected to lightning or
slashing damage, it splits into two new puddings if it has at least 10 hit
points. Each new pudding has hit points equal to half the original pudding's,
rounded down. New puddings are one size smaller than the original pudding.

Adult Black 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 Black Dragon regains spent legendary actions at the start of their turn.

Detect.The black pudding dragon makes a Wisdom (Perception) check.

Tail Attack.The black pudding dragon makes a tail attack.

Wing Attack (Costs 2 Actions).The dragon beats its wings. Each creature within 10 ft. of the dragon must succeed on a DC 19 Dexterity saving throw or take 13 (2d6 + 6) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.