UNDERTALE: How to Enter Sans's Room

Conditions for Unlocking Sans's room

Clearing Papyrus's friendship event

To go to Sans's room, clear Papyrus's friendship event without defeating Papyrus. If you become friends with Papyrus, you can freely enter and exit Papyrus's and Sans's houses.

Conditions for triggering Papyrus's friendship event

Proceeding to New Home in the Neutral Route

To go to Sans's room, you need to receive the key to the room from Sans's judgment. Sans's judgment is an event that only occurs in the Neutral Route, so proceed to New Home after the Mettaton EX battle.

Guide to the New Home in the Neutral Route

Not undergoing Sans's Judgment

The key to Sans's room can be obtained by repeating Sans's judgment. Once you undergo the judgment and save, you will not be able to trigger the event to obtain the key.

How to Obtain the Key to Sans's Room

Save only Before the First Judgment

To obtain the key to Sans's room, save only before the first judgment at the save point called Last Corridor. By saving at this judgment point, you can smoothly obtain the key. Be careful not to proceed too far after the judgment and accidentally save, as it will remove the conditions for obtaining the key.

Repeat the Process of Loading after Each Judgment Three Times

To obtain the key to Sans's room, repeat the process of receiving judgment from Sans, exiting the game, loading again, and receiving judgment again. During the second judgment, obtain the Secret Codeword, during the third judgment, obtain the Secret Secret Codeword, and during the fourth judgment, obtain the key to Sans's Room.

How to Enter Sans's Room and Laboratory

Investigating Sans's Room

To enter Sans's room, you need to obtain a key and then investigate Sans's room. Once inside, examine the drawers to find the Silver Key, which allows you to enter the hidden room known as Sans's Laboratory.

Accessing Sans's Laboratory from the Outside

After obtaining the Silver Key inside Sans's room, go outside and head towards the left side of the house. Investigate the end of the hidden passage to use the silver key and gain access to Sans's Laboratory.

What is Sans's Room?

Sans's Room is on the Second Floor, Right Side of Papyrus's House

Sans's room is located on the second floor, on the right side of Papyrus's house. You can't enter just by becoming friends with Papyrus, but once you receive the room key from Sans, you can come and go freely.

A Fun Easter Egg and Hidden Element

Sans's room and Sans's laboratory are one of the fun Easter eggs and hidden elements that don't affect the story. It's not necessary to visit them, but if you want to fully enjoy UNDERTALE, it's worth paying them a visit.

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