Skaven

The Skaven are rat-people who were made in a lab. They are often found deep underground, but are not found in groups, instead they live as individuals. Since their offspring are rarely Skaven, most of their life's goal is find a mate and have as many children as possible.

Those who chose not to mate, often go on wide-spread adventures causing mischief and angst. They are very much scavengers and take what's not theirs all the time.

Since they live deep beneath the ground, often in sewers, they find trinkets and items just dropping in above them.

In historic times, the Skaven were thought to have been once overlords claiming land and overtaking it, but since they like to surround themselves in thieves to gain more trinkets and items, they were overthrown and cast into the sewers and deep depths.

They are not the most charismatic of species, but they can be very intelligent diplomatically. However they were made originally was intended to be incredibly smart.