Santoryu (3 Sword Style)

Three Sword Style is a unique style of triple wielding swordsmanship where the practitioner wields three katanas; one in each hand and the third in the jaw. This fighting style is a grueling process to learn having to strengthen your teeth, jaws, neck and arms to extremes in order to use it. Three Sword Style is an extremely formidable Strong Blade swordsmanship style in comparison to conventional swordsmanship such as one sword style or the more versatile two sword due to triple wielding three swords by dual wielding two sword in both hands and the third in the mouth. While using Three Sword Style, users have a tendency to hold the left hand blade with a "reverse grip", in which the blade protrudes from the bottom of his hand and points away from the opponent. This is likely done to increase the versatility of their attacks, as holding the blade in this fashion allows them to deliver multiple cuts from a variety of angles.

3 weapon fighting

2 weapon fighting allows you to attack 2 times instead of 1. when drawing your weapons, you can draw your third weapon at the same time as your second weapon.

Kenbunshoku haki

you gain proficiency in perception, you also gain 10 feet of blindsight

Busoshoku haki

you can add modifiers to both attacks in 3 weapon fighting.

3 Sword Counter

Twice per short rest, you gain the ability to use your reaction to attempt to knock your opponent's attack away and then strike with the blade in your mouth, when you activate this ability you roll your attack at the same time as your opponent to compare with your opponent, whoever rolls the highest is allowed to roll damage on their attack, if both roll the same then neither get to roll damage.

Improved Critical

you have sharpened your skills when attacking with you swords to the point that when rolling to attack, if your dice lands on anything above a 17 (not 17 itself), you can roll critical damage for the attack rather than normal damage

Haōshoku Haki

the will of a conqueror you harbour has allowed you to create powerful shockwaves when you attack that cut into your opponent's willpower itself, on your first attack every turn your opponent must succeed a DC 16 constitution saving throw or be knocked prone.