Long ago, a half-dragon trained a group of warriors to aid in her efforts to carve out an empire for herself. She failed but the esoteric techniques she taught these soldiers has been passed down from mentor to student ever since. Unlike joining other fight clubs, pugilists do not become discover these abilities due to temperament or inclination alone. Instead, dragonhearts, as these pugilists are known, dedicate themselves to learning the ancient combat techniques taught by the half-dragon would-be conqueror.
When you choose this fight club at 3rd level, you carry yourself with the menacing confidence of dragons. You gain proficiency in the Intimidation skill if you don't have it already. Your proficiency bonus is doubled for any ability check you make that uses this proficiency.
In addition, you can read, speak, and write Draconic.
Also at 3rd level, you can use a bonus action on your turn to cause your skin to slough off, temporarily revealing hard scales underneath. When you do, you have resistance to bludgeoning, piercing, and slashing damage for 1 minute.
Once you use this feature, you must finish a short or long rest before you can use it again.
At 6th level, when use your Bloodied but Unbowed feature you can choose to exhale a 30-foot cone of elemental energy as part of the same reaction. When you do, you can choose the nature of your breath weapon which determines the type of damage dealt: acid, cold, fire, or lightning.
Each creature in the area of exhalation must make a Dexterity saving throw with a DC equal to 8 + your Constitution modifier + your proficiency bonus. Creatures who fail this saving throw take 1d12 + your pugilist level damage, and half as much on a successful one.
At 11th level, when you use your Scales of War feature you also sprout wings, giving you a fly speed of 60 feet for 1 minute.
At 17th level, as an action you can exude terror to each creature of your choice within 60 feet. Chosen creatures must make a Wisdom saving throw with a DC equal to 8 + your Constitution modifier + your proficiency bonus. On a failed saving throw, the creature becomes frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on a success.
Once you use this feature, you must finish a long rest before you can use it again.