Sword of Sacrifice (Patreon)

Weapon (any sword), rare (requires attunement)

You gain a +1 bonus to attack and damage rolls made with this magic weapon. When you take the Attack action, you can forgo one of your attacks to wound yourself with the sword instead. When you do, you take 1d6 + 1 necrotic damage, which can't be reduced or prevented in any way. Then, choose a creature that you can see within 60 feet of you. That creature becomes cursed by the sword for 1 minute or until your concentration ends (as if concentrating on a spell). The curse ends early if you end one of your subsequent turns without attacking the creature with the sword. Whenever you hit the cursed creature with the sword, it takes an extra 1d6 necrotic damage from the attack. If you slay a cursed creature with the sword, you regain 1d6 + 1 hit points. Dying doesn't end your attunement to the sword.

Sacrifice. As an action, or as a reaction when you're reduced to 0 hit points, you can use the sword to end your life in an act of total sacrifice. When you do, you are killed outright, but the sword becomes a dancing sword that you control on your initiative count. The sword uses your attack bonus and ability modifier for its attack and damage rolls, and it has a +1 bonus to those rolls. The sword drops to the ground next to you and becomes a normal sword of sacrifice after 1 minute or if you're returned to life. Making more than four attacks with the dancing sword doesn't end the effect early. The sword deals an extra 1d6 necrotic damage to any target it hits for the duration. Once you've used this property of the sword, you can't do so again.

The knight's strength was leaving him. His body felt cold. He watched in horror as his foe advanced on his ward, defenseless to protect themself.

But he was unable to stand.

Years ago, he swore to use his life to protect theirs. Today, he knew the cost was due. With the last of his strength, he plunged the blade into his chest and poured his lifeblood into its metal.

As his eyes closed, he could only mutter, "Keep them safe...please," as the blade rose and carried out the last of his mortal oath.