Greatwielder

A Greatwielder's weapon often dwarfs them in size. Giant blades, massive hammers and mauls, greatwielders swing these as though they were the lightest rapier.

One-Handed Style

Starting at 3rd Level, you are able to use the most unwieldy weapons with ease. You gain proficiency in all Heavy and Two-Handed melee weapons and you may hold and attack with a Heavy or Two-Handed melee weapon as though it did not have those properties. This can only apply to one Heavy or Two-Handed weapon at a time. When you make a melee attack wielding a Heavy or Two-Handed weapon in this way and miss, you gain 5 extra feet of movement this turn and you don't provoke opportunity attacks from that creature for the rest of this turn. If you do hit, you may use your bonus action to push that creature up to 10 feet away from you.

Giant's Strike

At 3rd Level, you have become so adept at using giant weapons in a single hand that you can wield them with both hands to swing with even more power than any ordinary fighter could.

When you take the Attack action while wielding a Heavy or Two-Handed weapon in two hands, you can use your bonus action before making the attack roll to make the attack a Giant's Strike. If the attack misses, that attack deals half-damage. If it hits, the creature must succeed at a Strength saving throw or be knocked prone.

You can use this action a number of times equal to your Strength modifier and you regain all uses when taking a short or long rest.

Robust Posture

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. 

You also gain proficiency in Intimidation and you have advantage on Charisma (Intimidation) ability checks while holding or carrying a heavy weapon.

Twin-Handed Style

At 10th Level, you have become adept at fighting with two unwieldy weapons at the same time for offense and defense. You may use two-weapon fighting with any melee weapons, and you may add your ability modifier to the damage of the second attack.

Whenever you hit a creature while holding a separate heavy weapon in each hand, you can choose not to add your ability modifier to the damage of the attack, and instead add your Strength modifier to your AC until your next turn.

Cleaving Strike

At 15th level, when you take the Attack action or attack using two-weapon fighting, you may have the attack target one additional creature within 5 feet of the original target, using the same attack and damage rolls.

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 roll the damage die for a heavy weapon that you are holding to reduce the damage that attack does by that much. If this would reduce the damage past zero, the attacker takes damage equal to the excess beyond zero in the damage type of your weapon.