Eldritch Fusil, Ostean
Your own blood shed when you were reduced to 0 hit points by a construct, undead, or inanimate object.
This arcane fusil was crafted with blood magic drawn from the plane Ostea. Carved from bone, the weapon has a scabrous crust clotting the interior of the barrel. It is a one-handed ranged weapon (range 20/60) that deals 1d10 piercing damage. The weapon deals an extra 1d6 damage against nonliving things like constructs, undead, and inanimate objects.
Similar to a traditional arcane fusil, this weapon requires no ammunition. However instead of evoking bolts of elemental energy, it creates and fires a bullet of your blood. It does not require a trigger charge, nor any sort of action to reload, and so can fire multiple shots in the same turn if you are capable of making multiple attacks.
Once you have attuned to and are wielding the arcane fusil, you can fire a number of shots equal to 1 + your Constitution modifier (minimum 1). These shots recharge after you finish a short or long rest. Any shots beyond these, as well as any shots fired if you are not attuned, also deal 10
damage to you. This damage cannot be reduced. It is possible for you to exsanguinate yourself into unconsciousness by overusing an Ostean fusil.
If you do not have blood you cannot use this fusil.