They are not faction specific, it'll take all the spheres/factions for that set that could be drawn for those 5 cards you get.
The usual pull is 2 ** and 3 *. I strongly suggest that if you are not aiming something that low rarity and you don't want to spend that much, don't buy the pack. It's best to save your gran (for a very long time) till some type of sale appears like PreBuilts, Faction Packs, and other better priced items
(╯◕◡◕)╯︵ ┻━┻ *Table flip!*
(ノಠ益ಠ)ノ 彡 （ヽ.□.）ヽ *Quit flipping my effin tables!*
ლ(ಠ益ಠლ) *Who's next?*