Deception

Here are the combinations for the invaders who are
otherwise unavailable.
When collecting bodies:
 
- Invite a merchant and a pirate : a pesky little
  carpenter will come with them
- Invite a general and a wizard : an annoying messenger
  comes with them
- Invite a magic doll and a psychic : a curious little
  alien tags along
- Invite a gem guard and a swordsman : a witch comes
  along with them