Some fighters specialize in multiple weapons. Others are practitioners of the bow. And then, there are those who develop a kinship with a single weapon, that chosen weapon becoming an extension of the fighter itself.

As an Weapon Master, you have selected a weapon to develop a bond with. Through your travels, you and the chosen weapon grow as one. In time, it is less a weapon, and more a partner; perhaps it is even like family.

Chosen Weapon

When you select this archetype at 3rd level, you can attune to a weapon of your choice, making it your chosen weapon. To do so, you must conduct an hour-long ritual that binds you to that weapon. You are proficient with it while you wield it. This weapon counts as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage. Once the hour ends, the chosen weapon takes on a dull blue glow, emitting dim light in a 10-foot sphere. As a bonus action, you can deactivate or reactivate this light.

While you are away from your chosen weapon, you can use an action to sense the direction of your weapon, as long as the weapon is on the same plane of existence as you. If the weapon is in motion, you know the direction of its movement. Any creature other than you that makes an attack with your chosen weapon does so with disadvantage, as the weapon will weigh 450 lbs when not in your hands.

You may only have one chosen weapon at a time. If you perform this ritual again on another weapon, the chosen weapon status of the first weapon is removed and reapplied to the new weapon.

Martial Symbiosis

You can use a bonus action to imbue your chosen weapon with part of your own will, providing it temporary sentience which lasts it is destroyed, until you dismiss it as a bonus action, or until you’re incapacitated. While sentient, your chosen weapon gains a flying speed of 30 feet.

Your weapon has an AC 14 + your proficiency bonus, 1 hit point, and immunity to all conditions. If it has to make a saving throw, it uses your saving throw bonus for the roll. On your turn, you can mentally command the sword to move up to 30 feet in any direction (no action required). Furthermore, your chosen weapon must remain within 30 feet of you, or it loses its sentience, and if it is flying it immediately falls to the ground. This is also the case if the weapon is successfully attacked.

You can use the weapon in the following ways:

• When you take the Attack action on your turn, any attack you make with that action can originate from your space or the weapons space. You make this choice for each attack.
• When a creature that you can see within 5 feet of your weapon moves at least 5 feet away from it, you can use your reaction to make an opportunity attack against that creature as if you were in the weapon's space.

• You can imbue a greater amount of your will into the weapon. Whenever you take the Attack action, you can make one additional melee attack from the weapon’s position.               You can use this feature a number of times equal to 1+ your Constitution modifier. You regain all expended uses when you finish a long rest. (Weapon Flow)

Weapon Sense

Instead of imbuing your will into the weapon providing it with a form of sentience, you can temporarily transfer your own consciousness to the weapon. As an action, you link your soul to your weapon and can see and hear through it. During this time, you are deafened and blinded. You can sustain this effect for up to 10 minutes, and you can end it at any time (requires no action). While your weapon is being used in this way, it can be up to 1,000 feet away from you without being destroyed.  

Unbreakable Bond

Starting at 10th level, When you roll initiative regain 1 use of 'Weapon Flow'. In addition, when your Chosen Weapon is within 10ft of yourself add your proficiency bonus {{proficiency}} to its attacks. 

Heavenly Martial Body

At 15th level, Your martial capabilities transcend that of your physical body, granting you proficiency in all saving throws. Additionally, gain the ability to implant some of your Martial Body's energy into another creature allowing you to end a negative status on them such as the charmed, frightened, or stunned condition (once per long rest).

Natural Sword

At 18th level, you have reached the level of saint and have entered a tri-unity between body, mind, and weapon. A state surpassing any other, becoming one with the world itself you can imbue aspects of nature into your sword as if it you were wielding the world in your hands. As a bonus action you can harness this power, gaining the following benefits for 1 minute: 

• Your immense will generates a great spiritual pressure in a 15 ft radius sphere around yourself. Each chosen creature in the sphere when it appears must succeed on a Strength saving throw against your spell save DC or be knocked prone additionally, creatures within the sphere have disadvantage on attack rolls made against you.     
• Your weapon can adapt to nature's elements, when you damage a target with an melee attack, you can change the damage type to force, cold, fire, lightning, or thunder. Additionally, when you change your damage in this way deal an extra 1d6 damage of the chosen type.

You can use a bonus action to end this effect. Furthermore once you use this feature, you can’t use it again until you finish a long rest.