True Sword of Kas

Kas is a powerful warrior who served Vecna for countless years and was rewarded for his loyalty with this sword. As the duo's power grew, Kas grew doubtful of his worth to the wizard. In his hubris, the sword amplified his darker emotions to urge Kas to destroy Vecna and usurp his throne. Vecna’s destruction came at Kas’ hand but Vecna also retaliated against his traitorous lieutenant, leaving only Kas’s sword behind. The true sword was lost, with replica Sword of Kas sent across the realities of the multiverse like the Eye and Hand of Vecna. In the hands of its owner or those with his blessing, the True Sword of Kas achieves its greatest potential. It has the following traits;

1. Bloodthirst. The sword thirsts for blood, demanding it on its blade within 1 minute of being drawn from its scabbard, its wielder makes a DC 20 Charisma saving throw. On a successful save, the wielder takes 3d6 Psychic damage. On a failed save, the wielder is dominated by the sword, as if by the Dominate Monster, and the sword demands blood. The spell effect ends when the sword’s demand is met. Only Kas, Vecna, and those with their blessing are immune to this effect.
2. Magic Weapon. You gain a +6 bonus to attack rolls and damage rolls made with the sword, which scores a Critical Hit on a roll of 18+. It deals an extra 1d10 Slashing and 1d10 Piercing damage to Undead.
   • Secret Message. Hidden in the blade and revealed within 60 feet of Kas or Vecna is the true origin of the blade. A CR 20 or higher creature can make out the words in their native language. When spoken aloud near Kas or Vecna, they are dealt 10d10 psychic damage ignoring immunity and resistance as the words strike their very soul. It reads;
     • "With this blade, you are my sword. The Right Hand that delivers my judgments. My will, with the eternity of resolve worthy of my attention. A piece of me for only your use. Now, and forever." 
   • Undead Icon. While attuned to the sword, you have immunity to Charmed, Frightened, and Poisoned.
   • Ambitious Resolve. While attuned to the sword your speed increases to 10 feet, and have immunity to Blinded, Deafened, Petrified, and Stunned.
   • Solitary Soul. While attuned to the sword, you kill any nonmagical vegetation you touch that isn't a creature. An aura of 30 feet extends from you that decays the life of all CR 1 or lower creatures. They are dealt 1d10 necrotic damage for every hour they are within proximity of the sword.
   • Improper Pairing. When you become attuned to the sword, you take 10d10 psychic damage. Only Kas, Vecna, or those with their blessing are immune to this property.

3. Spells. While attuned to the sword, you can cast the following spells (save DC 18) from it at the highest level. The sword is used as the casting source:

   • Abi-Dalzim's Horrid Wilting
   • Blade of Disaster
   • Call Lightning 
   • Divine Word
   • Finger of Death
   • Storm of Vengeance

   Once you use the sword to cast a spell, you can’t cast that spell again until the next dawn.

4. Spirit of Kas. While the sword is on your person, you gain the following benefits:
   • Battle Hunger. You add 1d10 to your Initiative rolls.
   • Blade of Defense. When you take an action to attack with the sword, you can transfer some or all of its attack bonus to your armor class instead. The adjusted bonuses remain in effect until the start of your next turn.
   • Necrotic Resistance. You have Resistance to Necrotic damage.

5. Sentience. The True Sword of Kas is a sentient, Neutral Evil weapon with an Intelligence of 17, a Wisdom of 15, and a Charisma of 18. It has hearing and Blindsight out to 120 feet. The weapon communicates telepathically with its wielder and speaks their native tongue.

6. Personality. The sword’s purpose is to bring ruin to Vecna, be it in person or anything of connection to him. Killing Vecna’s worshipers, destroying his works, or foiling his machinations all help to fulfill this goal. This is rooted in the sword having manifested the scorn and betrayal Kas felt by the Lich by their former affections. Like Kas, it feels like the Lich cares nothing for it, and uses everyone and anything to achieve his ambitions of godhood.

   • The True Sword of Kas always seeks to destroy anyone corrupted by the Eye and Hand of Vecna. It has a pull to these items on the same plane as it, able to be a compass to their exact location due to the trio's connection to one another. 

7. Destroying the Sword. A creature attuned to both the Eye and Hand of Vecna can use the [spell] Wish[spell] property of those combined Artifacts to unmake the True Sword of Kas, provided the sword is within 30 feet of the spell’s caster. Upon casting Wish, the creature makes a DC 20 Charisma saving throw. On a failed save, nothing happens, and the Wish spell is wasted. On a successful save, the True Sword of Kas is destroyed.

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, Bonus: Initiative, Weapon Property: Finesse, Proficiency: Longsword, Damage, Buff, Debuff, Combat, Cursed/ , Versatile, Sap