Vampiric King's Greatblade (5e Equipment)
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Weapon (greatsword), legendary (requires attunement by a vampire or a creature with vampire blood(vampire spawn, dhampir, ect.))
Each time this sword becomes bound to a new master, the shape of it changes slightly to better suit the user. You have a +2 bonus to attack and damage rolls with this magic weapon. In addition, the weapon deals 2d6 additional slashing damage while you are in dim light and darkness.
Blade of the Old King. The blade is invisible and covered in black mist in sunlight and only shows its true form in dim light or darkness.
Blood Sucker. You recover hit points equal to half of the additional slashing damage dealt with this weapon.
Pure Night. As a bonus action, the user may cast the darkness spell through the blade without the need for material components. When the cast the spell in this way, you can see through the magical darkness created by this spell. This effect may be used 2 times, and this weapon regains all expended uses at dawn.
Blood Shield. Whenever a non-construct or undead creature that has blood dies while within 60 feet of this blade, you may have the blade create a blood shield around a target creature you can see within 60 feet of you. The target creature then gain temporary hit points equal to 1d6 + the slain creature's CR.