Kill a Sim and wait for the Grim Reaper to appear. Plead for his or her life. The Grim Reaper will either ignore your plea, turn your Sim into a Zombie, or revive your Sim. If your Sim was revived, kill him or her again, then try again. The outcome is random. Note: Do not save the game if the Grim Reaper kills your Sim. Reload the game and try again. Zombie Sims do not have any features different from normal Sims other than a green color.