(Feel free to make your own)

Sanghai

These are aliens made entirely out of goo. They usually take form of humanoids but can take any form they wish. It's also hard to kill them, as you'd need to reach into them and grab their heart -- their only organ. These creatures frequently escape prison and aren't taken on hunting our bounty missions considering their weak strength.

Geths

These are stereotypical aliens -- big foreheads, tiny bodies. They are incredibly small, usually only 7-8 inches tall. They're speedy and hard to catch, but also easy to see. Unlike the Sanghai, they are very colorful.

Jnats

These are huge and heavy creatures. They are known for short tempers and heavy punches. If they don't beat you to a pulp with their fists, though, then they'll kill you in one bite. Their fists are usually double the size of their head, and their mouth and fangs takes up most of its head. It has no nose and its eyes are very tiny, so sight and smell are practically useless to them.

Eredees

These are creatures similar to humans, except much smarter. They on average lack physically, however, so it takes a lot of training for them to become warriors. They are good leaders, and the Eredee in the High Commission is the leader of the H.C.