Heavy Weapon Fighters are taught the how to wield weapons larger than themselves at a very early age. In order to build the muscles needed to wield these great weapons, they have to start early and complete harsh training regimens that break down and rebuild the body. However, the training bears many fruits of labor as they are able to wield the largest of weapons with ease. They are unmatched in battle, showcasing their hearty constitutions and overwhelming strength to those around them. 

Heavy Weapon Mastery

Starting at 3rd Level, you are able to use the heaviest weapons with ease. You gain the following benefits:

• You ignore the two-handed and heavy properties and are able to wield a heavy weapon with one hand, however, this may only apply to one weapon at a time
• When making a melee attack and the attack misses, your movement speed increases by 5 feet for this turn and you do not trigger attacks of opportunities from the creature that you attacked
• If you hit with an attack, you may spend a bonus action to push the creature 10 feet away from you
• When you attack with a heavy weapon using two hands, you deal an additional damage die for that weapon

Giant's Strike

Additionally at 3rd level, you can use your bonus action to turn an attack into a Giant's Strike, as you swing your weapon with such force that the ground beneath the creature begins to crumble and break. Each creature within 10 feet of the creature hit must make a Strength saving throw or be knocked prone. Creatures that are knocked prone take an additional 1d8 bludgeoning damage.

You can use this feature a number of times equal to your Strength modifier per Long Rest

Robust Build

At 7th Level, you have honed your strength to maximize your ability to handle larger weapons and objects. You may treat your size as one size class higher when lifting, pushing, or grappling.

Additionally, you gain proficiency in the Intimidation (Charisma) skill, or expertise if you are already proficient.  

Two-Weapon Style

At 10th level, you become adept at wielding heavy weapons using a two-weapon fighting style. When you make an extra attack as a result of using a weapon that has the heavy property, you can add your ability modifier to the damage of that attack if you aren’t already adding it to the damage.

Additionally, when a creature hits you with a melee attack while you are dual wielding heavy weapons, you may can use your reaction to temporarily bolster your defenses and add your Strength modifier to your AC until the start of your next turn. You can use this feature a number of times equal to your Strength modifier (minimum of 1) per Long Rest.

Heavy Strikes

At 15th level, your weapon attacks score a critical hit on a roll of 18–20.

Steel Wall

At 18th Level, you can use heavy weapons to stop the most grievous attacks. Whenever a creature hits you with a melee attack, you may use your reaction to reduce the damage you take by rolling 1d10 + Strength modifier + Constitution modifier. If this would reduce the damage you take past zero, the attacker takes damage equal to the excess. Damage type is determined by the attacker's weapon damage.