Executioner

You are Judge, Jury, and most importantly Executioner. You punish the wicked for their transgressions and execute them accordingly.

Driving Strike

Beginning at 3rd level, when you attack a creature with enough force you know how to drive your weapon deeper into your target. While attacking with a melee weapon whenever you roll a critical hit or when you roll damage and one of the die results in its highest possible result, roll another die of the next die size down and add that number to the amount of damage dealt.

Once you reach 10th level when you are rolling your extra die you roll the same die size as the weapon you are using.

Know Thy Enemy

Also at 3rd level when a creature that you can see within your melee weapon's range targets you with a melee attack, you may use your reaction to make a wisdom(insight) or intelligence(investigation) check vs a DC of 10 + the attack bonus of the triggering attack. This check is made with advantage if you have dedicated a total of 1 hour within the past 24 hours carefully observing the target. If you are successful, that attack has disadvantage. If you succeed by 4 or more, you may either make a free melee weapon attack against that creature with advantage, or shove them 5 feet in a direction of your choice if they are medium or smaller. Starting at 15th level you gain a critical range of 18-20 against the target if you study the target for a total of one hour within the past 24 hours

Pursuit

At 7th level you gain proficiency in the Insight and Investigation skills if you don’t already have it. Your proficiency bonus is doubled for any ability check you make that uses either of those proficiencies.

Bide Your Time

Starting at 10th level you can fight defensively and bide your time during combat to give you the time you need to read an opponent's moves. When you take the dodge action, you may choose a creature that you can see within 60 feet of you at the end of that turn. You then have advantage on all attack rolls you make on that creature during your next turn if the creature has not left your sight.

Executioners Vitality

After taking damage you can use your reaction to heal for 3d10 + your fighter level. This comes back on a Long Rest

Execution

Starting at 18th level you have become deadly enough to try and kill a creature almost instantly. As a bonus action, choose a creature you can see. Until the end of your turn, that creature has vulnerability to damage dealt by your attacks. However, if the creature has resistance to the damage type dealt by your attack, it loses that resistance until the end of your turn but does not suffer vulnerability. This feature does not bypass any damage immunities the creature may have.