When a Kensei wields a blade, they are legendary for the deadly precision that they wield their weapons with. But there are a few out there who have shunned the elegance of a smaller weapon and have instead taken up the challenge of wielding great weapons with all the grace and power of a mighty typhoon.

This subclass and features in this class are taken from u/SethBlackwood on Reddit.

 

 

Great weapon

At 3rd level, when you chose this tradition, choose a melee weapon that has the heavy property. You gain proficiency with the weapon if you don't already have it. This weapon counts as a monk weapon for you. Many of this tradition's features work only with your heavy weapons. When you reach 6th, 11th, and 17th level in this class, you can choose another type of weapon.

Sweeping wind: If you are wielding a heavy weapon that does not have the reach property, you can target up to two creatures that are within reach when you make an attack with your heavy weapon. If you do this, you do not add your ability modifier to the damage rolls.

Steel Fanged Viper: If you are using a heavy weapon that has the reach property, you can spend a ki point to increase the reach of your heavy weapon by 5 feet until the start of your next turn.

Weapon guard: If you are using your heavy weapon, and you use patient defense, you gain a +2 bonus to AC.

 

Great Precision

At 6th level, you extend your ki into your heavy weapon, granting the following benefits.

Magic edge: Your attacks with your heavy weapons count as magical for the purpose of overcoming resistance and immunity to non-magical attacks and damage.

Impact Strike: Whenever you hit a target with an attack with your heavy weapon, you may spend up to 3 ki points to attempt an impact strike. The target must make a strength saving throw or be pushed back 10ft for each ki point spent.

Shattering Momentum

At 11th level, whenever you attack a target with your heavy weapon you can spend 2 ki points to mark the target for one minute. The next time you hit the marked creature with your heavy weapon, you add an additional 1d6 to your weapon damage roll. Each time you hit them with an attack afterward, you add one additional d6 to the attack to a maximum of 3d6. If you miss an attack, end your turn without making an attack against the marked target, or attack a different target, you reset the extra damage to 1d6.

Unstoppable Strikes

At 17th level, whenever you make an attack with your heavy weapon and miss, you can spend a ki point and roll the weapon damage you would have done if you had hit and deal half the damage to the target. The attack still counts as having missed for the purposes of on hit triggers and effects.