Mill three cards, then you may return a creature card from your graveyard to your hand. (To mill three cards, put the top three cards of your library into your graveyard.)
"The distraction of your life has ended. Now your service begins."
—Kalitas, thrall of Ulamog
Because Corpse Churn doesn't target the creature card in your graveyard, you may choose one of the three cards you put there from your library if applicable.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.