Suns of Mandalore
Originally part of the Alpha-class of clones, trained by Jango Fett personally, Quicksilver went on to become an instructor for clones himself.
He was part of the Republic supported Inglorious Blasters cell, which sought to liberate Mandalore without a costly invasion.
After the war he stayed with the Empire for a little, but as the Clone Troopers were phased out, he found himself lost and disillusioned. After getting touch with one of his old squadmates, Wyvern, he ended up joining Clan Bes’uliik.