Vampiric Crimson Blade of the Pact

Dagger, Very Rare (Requires attument by Warlock/Sorcerer)

This brownish-red dagger has thorns on the blade edge, almost like a cervical bone structure. While attuned by a warlock or sorcerer this blade displays a faint purple bright on his reflection and is always cold to the touch, even if it’s thrown to fire will remain cold to touch.

While holding this rod, you gain a +1 bonus to spell attack rolls and to the saving throw DCs of your warlock or sorcerer spells.

In addition, you can use an action to make an weapon attack with this dagger, if it hits, it deals 3d10 necrotic damage, all the damage that the creature receives, the attacker recover his hit points. You can’t use this property again until you finish a short or long rest.