Acharn

Acharn was created by an extraordinarily powerful wizard. It was designed for an ancient king who lost his family to a powerful demon lord. Using Acharn the king was able to slay the demon, but he was unable to truly control the power within Acharn. He was driven mad and returned to the wizard and murdered him in cold blood. As he was dying, the wizard placed a curse on the king and Acharn. Anyone who uses the weapon to take the life of an innocent person will lose there life but their spirit will be tied to the blade. They will spend their afterlife waiting to find someone worthy to take up Acharn, and warn them of the dangers of the weapon. Only then can their spirit rest.

Acharn has a unique design. It is a single weapon consisting if two swords attached together with a chain of shadows. This chain of shadows can increase in length as necessary up to 30 ft. Acharn's design gives the wielder advantage against being disarmed.

Acharn can only serve one master at a time. The attunement process requires a special ritual performed at two of the ley-lines the extend through the Sword Coast.

Acharn will attune with anyone it believes can help it accomplish its goal, which is to seal powerful evils within its blades. If its wielder refuses to seal beings Acharn warrants sealing, the wielder must make a charisma saving throw or be forced to do Acharn's will. If this happens the wielder loses the ability to use any of Acharn's abilities until Acharn deems the wielder worthy.

Acharn has one seal on one its blades for each exceptionally powerful evil being it has destroyed (1d6 + 1). The first seal always grants a +1 bonus to attack and damage rolls made with this magic weapon. Each seal beyond the first grants Acharn an additional property.  Acharn can have a maximum of nine seals. The DM chooses each property or determines it randomly on the Acharn Properties table.

Every time Acharn deals damage, one of its seals begins to glow. Activated seals can be expended to cast a spell from the warlock spell list. The level of spell is equal to the number of seals expended. Seals can also be expended for a +1 bonus to attack and damage rolls per seal until the end of the round. Expended seals can not be reused until the wielder communes with Acharn over a long rest.

Acharn Properties

d100	Property
01–60	Increase the bonus to attack and damage rolls by 1, to a maximum of +3. Re-roll if Acharn already has a +3 bonus.
61–70	Kills with an attack involving Acharn restore one expended spell slot.
71–80	Acharn's damage range increases to 1d8 for each blade.
81–82	Acharn can be used as a ranged grapple up to 30 ft away. While grappled with Acharn, as a bonus action, you can attempt to pull the target up to 10 ft towards you.
83–84	Acharn shares life essence with its wielder. Effects that cause its wielder to lose temporary hit points are split evenly with Acharn.
85–87	When you hit with an attack using the Acharn, the attack an extra 1d6 slashing damage.
88–90	The Acharn scores a critical hit on a roll of 19 or 20.
91–92	Damage inflicted with an element matching one Acharn is currently amplified with deals an additional 1d6 damage.
93–96	Acharn functions as if the person wielding it has the dual wielder feat. If the person already has this feat they gain a bonus +2 AC
97–98	Acharn can store elemental energy. When taking damage from any element, Acharn stores half of the damage. The damage is released on the next attack, only one set of energy can be stored at a time. This does not reduce the amount of damage taken.
99	You can use an action to create a mirror image of Acharn that you control. Its attacks use your modifiers attack rolls but gain no bonus to damage rolls. Moving the weapon requires a bonus action.
00	The Acharn functions as a vorpal sword.

Sentience

Acharn is a sentient chaotic neutral weapon with an Intelligence of 12, a Wisdom of 10, and a Charisma of 12.  The DM may decide to roll stats for the weapon.  It has hearing and darkvision out to a range of 120 feet.

The weapon communicates by transmitting emotions, sending a tingling sensation through the wielder’s hand when it wants to communicate something it has sensed. It can communicate more explicitly, through visions or dreams, when the wielder is either in a trance or asleep.

Personality

Acharn feeds on the sorrow and vengeance of its wielder. If the wielder is put in a grave situation, the wielder must make a wisdom saving throw or temporarily lose sight of himself and his values.

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

Notes: requires a special ritual performed at two of the ley-lines the extend through the Sword Coast, Damage, Buff, Combat, Sentient, Finesse, Light, Vex