Favourite Monster (Immortal/Outsider)
"Astral stalkers are abominations created during the Dawn War by the gods as weapons. Devious and bloodthirsty killers, astral stalkers have served since the Dawn War primarily as bounty hunters and assassins, though they often hunt simply for the sake of the challenge in cornering a dangerous prey"
Favourite Monster (Elemental/Plant)
So yeah, any will do - i'll find a way torment my players with them.