The Soul of Taldorei

The Soul of Taldorei is an ancient and powerful artifact weapon formerly in possession of the player character party.

It's true nature is that of Graz'Tchar, the Decadent End, a sword once wielded by Graz'zt, a Demon Prince of the Abyss.

the shining greatsword is inlaid with rubies and silver, striking a beautiful cruciform image. True sight reveals it to be a rusted and pitted sword, dripping with acid and billowing noxious gas.

The sword bears the following properties
 * Requires attunement
 * grants a +3 bonus to attack and damage rolls
 * When a humanoid is hit with this weapon the wielder can force them to take an additional 3d6 radiant (actually poison) damage and make a DC 14 charisma saving throw. If they fail this save they become charmed for one hour, during which time if they are attacked again they take an additional 10d6 radiant (poison) damage ending the charm immediately. If the charm is ended this way they cannot be charmed for another 24 hours
 * The weapon is sentient and speaks to its wielder telepathically in the voice of a sorrowful old king, urging them to root out corruption across Taldorei and seize their destiny. (the voice is actually an

The sword has been shown to do the following
 * Attempt to dominate the mind of its wielder if its actions do not coincide with the swords wishes.
 * Billow a sickly green smoke that seems to evaporate after a few feet
 * Forcibly withhold power from it's wielder
 * Summon Hezrou demons
 * Summon "ghosts"