The Eternity Ring was created by Tilda, as a copy of the Infinity Ring for the SQ. She stole the Infinity Ring in Behind Enemy Lines and used Sera's DNA (through hair samples) to return to the future and create the Eternity Ring. It was damaged by Dak in Behind Enemy Lines, and was destroyed in The Iron Empire when Riq smashed it, splashing himself with mysterious fluids.
The Eternity Ring was described as looking like the Infinity Ring, but made of blue metal and glowed whenever someone grabbed it. It was also described as having an amber liquid for fuel.