Martial Master

When you pick this subclass at third level, you gain the ability to switch your fighting style once per long rest. 

Switch Fighting Style

Beginning when you choose this archetype at 3rd level, you can change your fighting style once per long rest. Starting at level 15, you can switch your fighting style twice per long rest. 

Versatile Warrior

Starting at 7th level, you gain temporary buffs when you switch fighting styles based on the fighting style you switched to. 

Fighting Style switched to:

Defense/Protection: +2 to hit and +2 additional damage on all attacks for 1 hour

Great Weapon Fighting/Two Weapon Fighting: +5 temporary hitpoints for 1 hour or until depleted

Archery/Dueling: +1 to your AC for 1 hour. 

Superior Training

Starting at level 10, switching to a particular fighting style grants you bonuses based on the fighting style. All buffs last for two hours. 

Archery: +2 to damage with all ranged weapon attacks. Additionally, for 1 hour, you gain the ability to critically hit enemies on a 19 or 20. 

Two Weapon Fighting/Dueling: +2 to hit and damage with all 1-handed weapons and versatile weapons wielded with one hand. 

Great weapon Fighting: +2 to hit and damage with all weapons wielded with two hands. 

Defense/Protection: +2 to hit and damage with the type of weapon (Ranged,1-hand,2-hand) you are currently wielding when you switch to these fighting styles. 

Weapon Master

Starting at 15th level, all buffs gained by switching fighting styles are increased by 2 and the buffs last for 3 hours as opposed to 1. 

Additionally, your improved training grants you the ability to switch fighting styles twice per long rest as opposed to once. 

Prodigy of War

At 18th level, your training has allowed you to use 2 fighting styles simultaneously. Additionally, your mind has become so attuned with weapons of war that you automatically switch to the two fighting styles best suited for use of any weapon you are currently wielding. 

Ranged weapon: Archery + Defense

Single 1 handed weapon + Shield: Dueling + Protection

Single 1 handed weapon + no shield: Dueling + Defense

2 1 handed weapons: Two weapon fighting + Defense

1 Two handed weapon: Great Weapon Fighting + Defense

No weapons: Defense + Protection

 

You may trigger this ability up to three times per long rest when you equip a different weapon. Otherwise, you may switch your fighting styles after 1 hour as before.

Archery

You gain a +2 bonus to attack rolls you make with ranged weapons.

Defense

While you are wearing armor, you gain a +1 bonus to AC.

Dueling

When you are wielding a melee weapon in one hand and no other weapons, you gain a +2 bonus to damage rolls with that weapon.

Great Weapon Fighting

When you roll a 1 or 2 on a damage die for an attack you make with a melee weapon that you are wielding with two hands, you can reroll the die and must use the new roll, even if the new roll is a 1 or a 2. The weapon must have the two-handed or versatile property for you to gain this benefit.

Protection

When a creature you can see attacks a target other than you that is within 5 feet of you, you can use your reaction to impose disadvantage on the attack roll. You must be wielding a shield.

Two Weapon Fighting

When you engage in two-weapon fighting, you can add your ability modifier to the damage of the second attack.