The Ringmaster had forged a ring with the power of a Cosmic Cube. He was defeated by a collection of heroes, ending with the Punisher shooting his ring finger. Captain America was en route to deliver the ring to S.H.I.E.L.D. when a M.O.D.O.C. Squad attacked. His belt was damaged and the ring fell during the fight.
The Cosmic Ring allowed Curtis Doyle to warp reality within a 15 feet (4.6m) around him, giving him a 30-foot sphere of reality he could alter. Curtis was able to use the ring to create various objects such as ice cream and his costume, change his appearance, allow him to fly, grant himself superhuman strength and durability, and use the ring's power to counter his paralysis in order to allow him to walk.
Crusader later took Curtis Doyle's ring to honor his dead friend.