It's literally called CUSTOM Xenians, meaning this is a made up xen creature.
This series was supposed to show off ideas of aliens that could be in the xen world itself,
but I already hated the idea after this post.

I think another one was "chewchawsk" or something and I cringed a month after posting.
Who in God's earth names a creature that...

this doesnt appear in half life OR half life: opposing forces, and i'm pretty sure you don't go to xen in blue shift so where is this from?