Meet Hired Gun and her small entourage of friends, Platinum Haze, Flare, and Serenity.

Hired is the silver buff looking Mare, Platinum is the Dark blue Alicorn, Flare is the Blue Pegasus, and Serenity is the little Pink filly on top of Hired.

this is from the Fallout Equestria Universe which is a rather large collection of fan-fiction where the land of the pony's is pushed into the post apocalyptic world of Fallout. It's a rather good set of stories!