Jackals

The Jackals are one of the three groups of raiders that originated from Vault 15, the other ones being the Khans and the Vipers. They eventually did not appear in any of the games, but they were mentioned by Aradesh once, in Fallout 1. They most likely came out of the Vault in the 2100s, as they are mentioned in the Burrows design documents as "a retreated group of humans who were later to become Jackals)" in 2106 (Fallout Bible #7).

They are your typical group of crazies. They have no morals except one: survival. They use group tactics to overmatch their enemies. They are craven cowards, though, and will not attack unless they know they can win. They band together in their hideaway and fight over the spoils.