To save your companion kill all zombies in the room then save and quit (do not leave room) and you want to save and then quit. Go back to you character and play, your companion is now alive.
How do I develop this? By working hard, I guess. I don't need any help with the development, but you can help me by telling your friends about my game. :)
ULTIMATE CHALLENGE! (Doing it as your read): Go on survival, pick a class (don't matter) then put brightness to -5 and no flashlight... have fun shitting yourself.
Please send me your full name and home address and phone number.