Iaijutsu Master

YOU CHOOSE THIS SUBCLASS AT LEVEL 1

 

A warrior who chooses to defeat their foes through focus and determination rather than a chaotic flurry of blows.

 

or whatever, I'm not the police, use your own flavor

 

I Have To Do It This Way Because DnDBeyond Has Weird Limitations

At Level 1: 

This you lose proficiency with Heavy Armor

At Level 2:  Sure Strike: This Ability Replaces Action Surge

When you take the attack action, but before you roll to attack you can decide to focus your fighting ability into a nearly sure hit, with the chance to hit an exposed area of your enemy for extra damage.

On your next attack roll a number of d20 equal to 2+(advantages-disadvantages), minimum of one.  Add your attack bonus to each roll.

For each hit you roll, you roll the normal damage for the attack.  For each 20 you roll, you roll 2 sets of damage dice, these do not count as critical hits for the purposes of feats and abilities.

Each hit counts as an individual hit for the purposes of additional damage that can be applied to all attacks in a turn, such at Great Weapon Master, Rage, STR/DEX Mod, etc.  Additionally, tacked on damage that can only apply to a single attack, such as Fury of the Small, Genie's Wrath, etc is applied only once at the end of the calculations.

If you roll all 20s it counts as a critical hit, and you deal maximum damage.

You may use this ability a number of times equal to your proficiency bonus per long rest, but only once per round.

You do not double sneak attack damage, and you can not use this ability with spell attacks.

At Level 3: Nerves Of Steel

You gain advantage vs fear effects and on initiative rolls 

Additionally you gain proficiency in intimidation and with calligraphy tools, you have expertise with both of these.

Heavy Handed

Before you make an attack roll you can decide to forgo any extra attacks you have gained through the extra attack action.  For each attack you do not take, add an appropriate damage die to the damage roll (i.e. 2d6 for greatsword).  

The total amount of dice counts as the damage dice for the purposes of critical hits and the Sure Strike ability.

Fast on Your Feet, Fast with Your Eyes

You gain +10 movement speed

Additionally, you may use a bonus action to gain the knowledge of the HP of an opponent you have struck during this round or the last.

Inured To Terror

You are immune to fear.

Additionally you may make one attack on the round that you are reduced to 0 hit points, you have advantage, and if the attack hits, it is a critical.  Sure Strike can not be used with this attack.

 

This does not use your reaction.

Inevitable

You can critically hit on a 19-20.

When you critically hit you double ALL damage that is applied to the strike

Sure Thing now doubles dice damage on a 19-20 and counts as a critical hit if all dice roll a19s and 20s