To become a contractor, you must first find a spirit willing to enter a contract with you. This spirit could take the form of a guardian deity of your village, the soul of a cherished friend, or even a being from another plane you managed to come in contact with. Through forming a bond with the spirit, a contract may be forged. This contract tethers the spirit's existence to yours, and allows you to wield the spirit's power in the form of a weapon which grows in power as your bond with the spirit grows stronger. Although be aware that angering the spirit may temporarily leave you without it's assistance. 

Contracted Spirit

A contractor is one who has form a contract with a spirit, weather that be one of the dead, a low level deity, or possibly a spirit from another plane which wondered into this one. Through the contract, the spirit takes the form of a magical weapon of your choice (this cannot be changed later). The contracted spirit has the following effects:

• Whenever you take any damage (other than Psychic) you still take the full damage, but the spirit also takes a quarter of the damage. While a weapon, the spirit cannot be damaged from any spells or attacks other than from this effect, or when you take a guard reaction. 

• When you are hit by an attack, you may use your reaction to guard part of the attack with your weapon, reducing any damage by half (other than Psychic), with the spirit taking the other half instead of the quarter damage it would normally take. 

• The spirit can change into weapon or back to a spirit with a bonus action. 

Glaive

Your contracted spirit can turn into a magical glaive. 

Greatclub

Your contracted spirit can turn into a magical greatclub.

Greatsword

Your contracted spirit can turn into a magical greatsword. 

Halberd

Your contracted spirit can turn into a magical halberd. 

Longbow

Your contracted spirit can turn into a magical longbow. 

Longsword

Your contracted spirit can turn into a magical longsword. 

Mace

Your contracted spirit can turn into a magical mace. 

Quarterstaff

Your contracted spirit can turn into a magical quarterstaff. 

Shortsword

Your contracted spirit can turn into a magical short sword. 

Trident

Your contracted spirit can turn into a magical trident that returns to your hand when thrown. 

Spirit Harmonize

Through your bond with your contracted spirit, you have gained the ability to harmonize with them, greatly strengthening the power of your weapon and granting a unique effect depending on the weapon. This effect lasts 1 minute and takes an immense focus. When taking damage while the effect is active, you must make a constitution saving throw with a DC equal to half the damage taken. On a fail, the effect ends. 

Spirit Harmonize: Ame-no-nuhoko

Your spirit harmonizes with you, transforming it into the legendary Ame-no-nuhoko. The powerful magic from this weapon can shape and mold the very earth, allowing you to cast Wall of Stone once per use of Spirit Harmonize, with the spell's concentration tied to Spirit Harmonize (one concentration check for both). You also gain access to Mold Earth while Spirit Harmonize is active.

Spirit Harmonize: Dyrnwyn

Your spirit harmonizes with you, transforming it into the legendary Dyrnwyn. The blade burns with fierce flames of justice, dealing 3d6 + strength mod + proficiency bonus fire damage. However the blade desires not to be used for an unjust cause, and will deal 2d6 fire damage to you as well if the creature attacked is of a good alignment. 

Spirit Harmonize: Fragarach

Your spirit harmonizes with you, transforming it into the legendary Fragarach. It's mighty blade is especially effective against armored foes as any non-natural armor is completely useless against Fragarach. When checking to see if Fragarach hit against any armored creatures, use either their natural armor (10 + Dex modifier) or unarmored defense when applicable. This effect does not apply to any creature listed as using natural armor, including Animated Armor.

Spirit Harmonize: Gáe Bulg

Your spirit harmonizes with you, transforming it into the legendary Gáe Bulg. This glaive deals 1d10 + strength mod + proficiency bonus slashing damage and 1d10 piercing damage from piercing barbs that stick into a creature hit by this weapon. A creature hit by this weapon must also succeed a DC 10 + dexterity mod + proficiency bonus or be grappled. 

Spirit Harmonize: Kaladanda

Your spirit harmonizes with you, transforming it into the legendary Kaladanda. This mighty club's blow cannot be easily softened by the creatures it strikes. While Spirit Harmonize is active, damage dealt by this greatclub ignores all resistances or immunities to bludgeoning damage.

Spirit Harmonize: Marmiadoise

Your spirit harmonizes with you, transforming it into the legendary Marmiadoise. This holy blade gleams with a searing radiant light capable of creating unhealable wounds. Creatures with a CR lower than your Fighter level damaged by this blade are unable to heal the wounds caused by any means, so long as Spirit Harmonize is active. A creature with a CR lower than your Fighter level killed by this blade can only be revived by True Resurrection or Wish while Spirit Harmonize is active. 

Spirit Harmonize: Pinaka

Your spirit harmonizes with you, transforming it into the legendary Pinaka. This bow produces it's own arrows capable of flying towards any creature you can see, even around corners or over walls. Attacks made with your Spirit Longbow ignore all cover while Spirit Harmonize is active.

Spirit Harmonize: Ruyi Bang

Your spirit harmonizes with you, transforming it into the legendary Ruyi Bang. This staff is capable of gaining an immense amount of weight in an instant. While Spirit Harmonize is active you may spend an action to shift Ruyi Bang's weight from 4lb to 17,550 lb. When Spirit Harmonize ends, the Spirit Quarterstaff returns to 4lb.

Spirit Harmonize: Sharur

Your spirit harmonizes with you, transforming it into the legendary Sharur. While wielding this magical mace, you feel lighter than the air itself. While Spirit Harmonize is active, you have a flying speed of 60 feet.

Spirit Harmonize: Trishula

Your spirit harmonizes with you, transforming it into the legendary Trishula. This mythical weapon glides through the air as easily as an arrow from a bow. While Spirit Harmonize is active, Trishula has the same range as that of a longbow, and returns to your hand instantly after it lands.

Enhanced Bond

Your bond with your contracted spirit has grown stronger through facing great adversity side by side. From this strengthened bond, so too does your contract strengthen, and in turn your spirit's weapon form. Your spirit's weapon form gains a +1 to attack and damage rolls. This increases to a +2 at level 18.

Greater Spirit

Through the experience your contracted spirit has gained, it has now evolved into a greater spirit. With this transformation, several of the spirit's normal abilities have been significantly strengthened:

When you are hit by an attack, you may use your reaction to block part of the attack with your weapon, reducing any damage by half (other than Psychic), with the spirit still taking the quarter damage it would normally take.

Iron Bond

Your spirit has been with you through thick and thin, through sadness and through joy. Through it all, your contracted spirit has stayed by your side, forging an unbreakable bond. Your spirit gains a +2 to attack and damage rolls while in it's weapon form.

Soul Bond

You've been together through it all, whether that be blood, sweat, or tears. Your souls are intertwined forevermore. Your spirit gains a +3 to attack and damage rolls while in it's weapon form and now when you are hit by an attack, you may use your reaction to block part of the attack with your weapon, reducing any damage by half (other than Psychic), with the spirit still taking the none of it would normally take.