Base Class: Fighter
Some fighters were born noble, they were trained from birth to ride and fight, they learnt pomp and pageantry, risen to be mighty warriors or trained lethal soldiers. Your path was written differently, learning through need and necessity, fighting in a different theatre of battle, trading war zones for street skirmishes, military tactics for gang warfare. You are at home in the back alleys, applying underhand techniques and drive to win no matter what.
Choosing this subclass will allow you to harass and weaken your foes, dealing swift attacks and knocking your enemies prone then grappling your foes into submission.
Throwing Hands
At 3rd level, you gain proficiency with improvised weapons and your battle scar-knuckles count as natural weapons. You can also make an unarmed attack as a bonus attack as long as you are not wearing heavy armor and wielding no weapons or only an improvised weapon.
Your unarmed attacks die use d6s. This increases to d8s at level 5, d10s at level 11, and d12s at level 17.
Knockout Punch
Starting at 3 level, you can focus your attacks into single, powerful punches, backed by the weight of your armor. Once a turn, while you are wearing heavy armor and have hit a creature with an unarmed attack, you can use a bonus action to force that creature to pass a Constitution saving throw or become knocked prone. The DC for this check is equal to (8 + your Strength modifier + your proficiency bonus).
If you hit the creature with more than one unarmed attack in the same turn, the creature has disadvantage on that saving throw.
Knockout
Once a turn, while you are wearing heavy armor and have hit a creature with an unarmed attack, you can use a bonus action to force that creature to pass a Constitution saving throw or become knocked prone. The DC for this check is equal to (8 + your Strength modifier + your proficiency bonus).
If you hit the creature with more than one unarmed attack in the same turn, the creature has disadvantage on that saving throw.
Aggressive Appearance
Starting at 7 level, you notice that other creatures hesitate to challenge your words when backed with your armored physique. You can add your Strength modifier to your Intimidation, Persuasion and Deception checks.
Steel Coated
At 10th level, your body has grown accustomed to being beaten, cut, and stabbed. When your Hit Points is below half of your maximum (rounded down) you take half damage from bludgeoning, piercing, and slashing damage. Your unarmed attacks have +1 bonus to their attack and damage rolls and are counted as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage.
Throwing With Force
Starting at 15th level, While wearing heavy armor, your unarmed attacks deal force damage. Additionally, if your target fails their saving throw against your Heavy Hitter feature, they are shoved 10 feet away from you in addition to being knocked prone. Your unarmed attacks have a +2 bonus to their attack and damage rolls and are counted as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage.
Adamantine Assault.
Starting at 18 level, your armored attacks can inflict traumatic head-injuries, destroying your target’s ability to think clearly.
If your target fails their Constitution saving throw against your Heavy Hitter feature, they have disadvantage on all attack rolls, saving throws and skill checks until the end of the encounter, in addition to all other effects. Your unarmed attacks have a +3 bonus to their attack and damage rolls and are counted as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage. Additionally, you score a critical hit with unarmed attacks on a roll of 19 or 20.