NS Kharaa

Here's the alien side of Natural Selection.

From left to right:

The gut munching, wall walking skulk.
The "fatty" gorge. Cute ickle guy, until you walk into his web and die from spit.
The fearsome lerk. Dunno what to say about it 'cept that ~kittah really really really has an obsession with them.
Fade. Blink in battle with him and he rips your guts out.
Onos. Big. Scary. RUN AWAY!

Please full view to see all four aliens