The Ring of Volthoom is an evil ring that draws its power from its owner, killing them from the inside out.
It has been considered to be the opposite of a Green Lantern Ring, feeding off of its wearer's fear as opposed to their willpower. Only by overcoming and subduing their fears can the Ring of Volthoom be put to rest, until such time that the owner lets his or her fears resurface.
When Volthoom was traveling the Multiverse and Timestream using the Travel Lantern, he landed in Earth 3, in which Mordru was living. Upon meeting, Mordru fused a piece of Volthoom's soul to create a power ring, the Ring of Volthoom.
Sometime within the recent past, the Ring of Volthoom found a host in the Abin Sur of Earth 3, then after he died the ring passed to the Hal Jordan of Earth 3. Soon this Hal Jordan traveled to Prime Earth during the events of Forever Evil, and was killed soon after. Upon his death, the Ring of Volthoom sought out a new host, and found one in Jessica Cruz.
During the final battle of the Darkseid War, Jessica Cruz (along with the Ring of Volthoom) jumped in the way of the Black Racer while he was chasing The Flash, and as a result the Black Racer seemingly killed Jessica and destroyed the Ring of Volthoom.
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