Lim-Dûls Gruft

If you have five or fewer cards in your library, you can pay 1 life as many times as you like, but you'll keep seeing the same cards.

If you pay no life, you shuffle the rest of your library and then put the top five cards back on top in any order.

In other words: — Step 1: Look at the top five cards of your library. — Step 2: If you like them, proceed to step 3a. If you don't like them, proceed to step 3b. — Step 3a: Shuffle the rest of your library, then put those five cards back on top of your library in the order you want. The spell has finished resolving. — Step 3b: Put those five cards on the bottom of your library in the order you want. Pay 1 life. Return to step 1.