| Cutie mark|
Not much of Eclipse's past is known, besides she lived in Stable 21 all her life, Dyna being her only friend.
When Stable 21's doors opened, Eclipse made a run for it with Dyna, only to panic at the realization that there was no longer a roof over head. She went into a vomitting fit as the two had a very brief chat with Watcher before setting off. They were caught in a crossfire, Dyna having to drag her to safety. She was the first to notice Dyna's cutie mark.
Eclipse is a white unicorn mare, with aqua eyes, and a rich purple mane that falls straight down.
Eclipse is generally wild, crazy, and somewhat Pinkie Pie-ish. She admits to Dyna that she is bipolar, her cutie mark representing it.
Dyna has not yet shown to be exceptionally talented in any realm.
Dyna's only current equipment is her PipBuck, a unique model, which she confides Dyna that there are only two, the two mares owning them both.
Eclipse is Dyna's closest friend, the two sharing a sisterly bond. Eclipse gave Dyna a PipBuck, which is a sister to her's, and easily makes her feel happy. The two will get occasionally get hostile with each other, but never without some humor in between.
- Eclipse appears in another Fallout: Equestria fic by the same author, titled Fallout Equestria: Eclipse, as an amnesiac alicorn taking care of an orphaned foal.