Shardblade (5e Equipment)

Weapon (longsword), artifact (requires attunement)

Each shardblade is an expertly crafted longsword that deals 2d8 points of damage, and no two look alike. Every one has its name or other designs engraved on the blade.
You have a +3 bonus to attack and damage rolls made using this magic weapon, on a natural roll of 14 or higher the blade deals double damage to living creatures with discernible anatomy if they are not wearing shardplate.
Soulshear. When you score a critical hit on a creature without a shardblade, if the target is at 40 hit points or less, it kills the target as long as it has no legendary actions, is your size or smaller, and has a discernible anatomy.
Each time you deal damage to a living creature, reduce its maximum hit points by the damage dealt. Shardblades do not reduce temporary hit points, they always deal their damage to a creature's natural hit point total.
In order to regain their lost hit point total, a player must be at their current maximum hit points and then spend hit dice during a rest, regaining the maximum hit points equal to the number rolled, up to your natural maximum hit points.
Bonded Blade. Once attuned, this weapon may be dismissed as a bonus action, disappearing into the æther. It can then be summoned as an action, appearing from mist in the wielder's hands. Once summoned, a shardblade remains as long as the owner wishes it to stay. It may be dismissed by the one attuned to it even if another creature is wielding it. If a creature who has attuned to a shardblade dies, the blade manifests at their side as though summoned. In order to willingly break your bond with a shardblade, you must summon it and let it go, willing away your connection. A shardblade may not be attuned to a creature if another living creature is already attuned to it.