Depends on the Alien
Big Chap would strike in the dark and end it
An Acheron Warrior would probably lose, as would the Queen, and the Runner certainly would lose the fastest
A Resurrection Warrior would probably have fun with Feral before killing him
A generic AvP Alien would be a tie, Grid Alien would stomp, the AvP Queen would tear Feral apart and scatter his remains all over the place
A bunch of AvPR Aliens would probably become paste, what with Feral enjoying doing exactly that
The Predalien has a chance
A Covenant Alien would be massacred