Saturn Dagger (5e Equipment)
From D&D Wiki
Weapon (dagger), uncommon (requires attunement)
A curved, single edged dagger with a purple blade, black hilt, and purple spike at the back of the handle. This dagger can hold 7 charges. As a bonus action, you can spend 1 charge to make 6 magical spikes orbit around dagger and the wielder's hand for 1 minute. Whenever you first hit a creature with a melee attack using this dagger while these spikes are out, your attack deals an additional 1d6 piercing damage. Alternatively, you can use the spikes for a ranged attack (range 20/60) that deals 1d6 piercing damage. This ranged attack does not require you to throw your dagger. Once either function is used, the spikes disappear until you spend another charge as a bonus action.
The dagger regains 1d6 + 1 expended charges at dawn.