You gain a +3 bonus to attack and damage rolls made with this magic weapon. In addition, the weapon ignores resistance to slashing damage.

When you attack a creature that has at least one head with this weapon and roll a 20 on the attack roll, you cut off one of the creature's heads. The creature dies if it can't survive without the lost head. A creature is immune to this effect if it is immune to slashing damage, doesn't have or need a head, has legendary actions, or the GM decides that the creature is too big for its head to be cut off with this weapon. Such a creature instead takes an extra 6d8 slashing damage from the hit.

This weapon is highly unique, as it is shaped by the soul of the one who wields it.

This weapon has three forms: Sealed, Shikai and Bankai, each one more powerful than the last.

Sealed Form: The weapon takes the form of the most significant weapon in your region, in most cases a Sword.

(Available from 8th level) Shikai: Upon passing a DC 10+Wis  Wisdom Check you can release your Zanpakuto's second form. (description to you or your Dms discretion) you also learn the name of your Zanpakuto, and this form can be used for 1d8+Wis hours before every long rest. gaining an additional +5 to your attack and one (Upto) 6th level spell (Available from any class spell list. NOTE: once your spell has been selected you can NOT pick another spell and it always cast at its max level)

(Available from 18th level) Bankai: Passing a DC 20 Wisdom Check you release the ultimate power of your Zanpakuto, it's appearance changing once again and gaining a +15 to your attack, and an additional spell upto 9th level (Not including Wish) 

Proficiency with a Longsword allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Bonus: Magic, Damage, Combat, Versatile, Sap