Rick brings Morty to a planet containing crystals that show whoever is touching them all the ways they may die depending on their choices.
Rick and Morty go to get some death crystals on a different planet that let you see ways that you can die. Morty steals one and goes crazy because the crystal shows a way that Morty can die with his crush Jessica. While that's happening Rick keeps on dying in the body of alternate versions of himself.—liamscwatt