Eclipse is a large, elderly, black tom with glossy fur, strong muscles, and bright amber eyes. His muzzle has grayed with age..
- After Winter dies, Eclipse is extremely grieved for he had believed she was a great leader, but pulls himself to his paws and moves on.
- Eclipse is with a couple rogues one day and he reveals that he had been raised in The Gangs, and when any cat mentioned it, he literally snapped their ears off. He hisses that Clan cats are just as brutal, and he shows them four ragged, deep scars in his throat.
- Eclispe meets Suchiwan one afternoon and the old tom warns Eclipse about coming rabid wolves, to kill the Clans and rogues. Eclipse chuckles and comments that wolves "ain't 'round no more." Suchiwan is slightly annoyed that the black tom won't take his warning seriously, and pads away.
- Eclipse manages to save a daring Hershey after the roof caves in the Twoleg basketball gym, during a tornado, but she comes out with fatal injuries. He rushes her to the forest where they meet Zack, Ivy, Eddie, and Twister, the survivors. Eclipse examines Hershey and announces that she is alive, but fatally injured with a broken spine. Ivy and Zack are wildly upset, and he suggests maybe that they should leave Hershey to die peacefully, but Eddie suggests that a vet lives nearby and could possibly save Hershey. The cats agree to this and take the little kit there.
Laidback, relaxed, loyal, and warm-hearted. When danger shadows over any cat, he will charge to the rescue, no matter what the cost.