Prerequisite: Alien
In a universe of war and hostility, there are many races that are unable to defend themselves, and suffer under the dominion of others. The Enslaved trait can mean that the alien is part of an enslaved race, such as the Ood, or even just a race that has been genetically created to serve others, such as the Pig Slaves that served the Cult of Skaro in Manhattan.
Enslaved means that the alien is part of a recognisably enslaved race. While the race may have been freed, they may still suffer the social stigma of their past, or they may currently be under the control of a dominant race. On top of being under the control of others, the alien will get a -2 penalty on all social rolls (usually involving their Presence or Resolve) when trying to voice their opinion because of their enforced subservient nature. Even if freed, it will take time to break their submissive attitude. It doesn’t mean it is impossible, there have been many occasions of vocal slaves leading a revolution, but they will have to overcome their subservience.