Actions

Multiattack. The dragon makes three attackes: one with its bite and two with its claws.   Bite. Melee Weapon Attack: +9 to hit, reach 2 sq., one target. Hit: 16 ( 2d10+4 ) percing damage and 7 ( 2d6 ) fire damage.   Claw. Melee Weapon Attack: +9 to hit, reach 1 sq., one target. Hit: 12 ( 2d6+5 ) slashing damage.   Hellfire Breath (Recharge 1d6>=5 ). THe dragon exhales hellfire in a 6 sq. cone. Each creature in that area must make a DC 16 dexterity saving throw, taking 42 ( 12d6 ) hellfire damage on a failed save, or half as much on a successful one.    

Bonus Actions

Alternate Form. A hellfire wyrm can assume the form a medium, large or huge tiefling or devil, or revert back to its original form.

Suggested Environments

Nine Hells of Baator