This fearsome ebony greatsword only reaches its true potential when bathed in the blood of the innocent.  Baseline, it deals 2d6 slashing damage (normal greatsword damage) and 2d6 necrotic damage.  Each time you deal damage to a creature with this blade, you regain health equal to half the necrotic damage dealt.  In addition, for every two good aligned creatures or creatures charmed by you you have killed with this blade, it deals an extra 1d6 necrotic damage.  This caps after you have killed 10 creatures (total of 7d6 necrotic damage).

This blade is a chaotic evil sentient weapon, with an Intelligence of 15, Wisdom of 12, and Charisma of 18.  It constantly drives its wielder to kill innocents, thus increasing its power.

This weapon has 5 charges, and regains 1d4 + 1 daily at dusk.  You can expend one charge as an action to cast charm person, with a DC of 18 if you don't have a higher one.

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

Notes: Damage: Necrotic, Based on the daedric artifact from TES V: Skyrim. The original enchantment reads: Absorbs the life essence of foes. Strengthened by the blood of deceit (for every two friends killed, the absorb health increases by 4, up to 30)., creature with any non-good alignment, Healing, Damage, Combat, Sentient, Heavy, Two-Handed