The Death's Scythe is a sword-type meleeweapon added in the Return to Castlevania DLC. Forces the spirit of enemies you killed to help you, summoning them as allies. They will target and explode on near enemies, dealing a Critical Hit.
Most enemies spawn ghosts, there are however few exceptions like Myopic Crows and Protector.
Like all weapons added in Return to Castlevania DLC expansion, Death's Scythe is based on the weapon from the Castlevania series. In this case, it is known under the same name.
Visually, no known version of Death's Scythe resembles one from Dead Cells except for the crude design, resembling his scythe in his second phase in aria of sorrow. However, half of it looks similar to one from Castlevania: Dawn of Sorrow.