if not using Sangromancy this spell is a Conjuration school
Casting Time: Bonus Action , Range: Self , Components: S (Somatic), Duration: -
Special Material: -
Effect
As part of casting this spell, you must expend a hit die or the spell automatically fails.
If you do, a writhing lash of coagulated blood springs from your hand. This magic weapon lasts until the spell ends. It counts as a simple weapon with which you are proficient, and it has the light, finesse, and reach properties. You can choose to add your spellcasting modifier, instead of your Strength or Dexterity modifier, to attack and damage rolls with this weapon. Its damage die is equivalent to the hit die expended casting this spell, and the damage dealt is necrotic. Each time a creature takes damage from this magic weapon, its maximum hit points are reduced by an amount equal to the damage it took.
At Higher Levels
When you cast this spell using a spell slot of 3rd or 4th level, when you take the Attack action, you can make two weapon attacks, provided both are with this magic weapon. When you use a spell slot of 5th level or higher, when you take the Attack action you make three weapon attacks, provided all are with this magic weapon
Lore, some nice lore flavour and/or history