How to (properly) spawn the Reaper

The game’s community considers the Yukiko Method to be the most well-known and easy way to spawn the Reaper. It consists of going to the 5th floor of Yukiko’s Castle and then returning to the entrance with a Goho-M. After that, you open up to 20 chests on the first floor of Yukiko’s Castle and return to the 5th floor. The Reaper will most likely appear in the second chest you open on that floor.

You can find a very detailed explanation of the Yukiko Method here, provided by king-guinevere.

The exact number of chests commonly associated with the method is 20. However, that is not entirely accurate — the actual number of chests you need to open can only be determined after you hear the chains during your exploration of the first floor. You must keep count until you hear the chains, then subtract 2 from that number, since the 5th floor always contains two chests.

Therefore, you should follow the Yukiko Method without specifically aiming for a count of 20 chests. Simply go to the first floor and keep track of how many chests you open until you hear the chains. Then reload your save and open the number of chests you counted minus two. After that, proceed as the Yukiko Method instructs.

1. Go to the TV World.
2. Enter Yukiko’s Castle and make your way to the 5th floor.
3. Use a Goho-M to return to the entrance.
4. Save the game.
5. Return to Yukiko’s Castle and go directly to the first floor.
6. Start opening chests until you hear the sound of chains. Keep track of how many chests you opened before hearing the chains.
7. Reload your previous save and return to the first floor of Yukiko’s Castle.
8. Open the number of chests you counted minus two. For example, if you opened twelve chests before hearing the chains, you must open ten chests after reloading your save.
9. Save your game.
10. Go to the 5th floor and open one of the two chests there. You should begin to hear chains, which indicates that you are on the right track. Open the other chest — the Reaper may appear there.
11. Reload your save and repeat step 10 if the Reaper does not appear.