Bone Weapon

You place your hand upon the surface of a corpse and its body twists and molds itself into a sickly weapon. When this spell is used on the corpse of a creature of size medium or larger, you create a Bone weapon in your free hand. This weapon can take the form of any simple or martial weapon and will take on its base stats with a +1 bonus to its attack and damage rolls.

When you kill a creature with this weapon you may use your reaction to give the weapon a +1 bonus to attack rolls and damage rolls. This reaction feature can be used to increase the weapons bonus up to a +4.

 At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the duration increases.