Whenever I play Undertale another time (anytime but the first run-through), after San's phone call, I can never get back to where I was because there is no save file. That means I can never go on a date with Papyrus, befriend Undyne, and go to the true lab.
I play on Switch. Can anyone help?


I'm assuming that you want to do a pacifist run after completing your neutral run. you can't befriend papyrus or undyne if you killed them, you have to reset your save and do a full pacifist run from the beginning, and it means that you can't kill any monster or boss, just spare them, and then you can befriend them.


the true lab is a part of the pacifist run that you go to after sparing every monster and tiring asgore until he shows the mercy button then talk to flowey.

if you killed any monster in your current run reset your save.

to just go to the true lab after beating asgore yo need the following prerequisites:

  • spared every monster and boss

  • spared asgore and talked to flowey (if you did a pacifist run, flowey will tell you to hang out with your friends)

  • if you killed any monster reset your save and begin a pacifist run

to go to the true lab you need to close the game after beating Flowey and then start it again and press continue in your save, you will find yourself at the save before asgore's fight, don't fight him, Go back until you get to the path between the core and MTT-hotel. You will receive a call from Undyne and she will tell you to go to Snowdin and deliver a message for her. When you take the message and deliver it to Alphys' lab you will swap it under the door. Alphys will think that's your message and you will date with her.

Go again to Alphys' lab and you will find a letter and a door. Then go to the real lab and finish it.

  • I already know that. It's just that after the Asgore boss fight, I spare him and then Flowey kills him. Then I get San's phone call, get sent into an empty room (in the ruins?), and then sees the credits (not necessarily in the right order). I can't go into the true lab and do whatever people do there. – Andy Yao Jul 12 at 0:35

Thanks for helping, but I actually got the answer. I went on a date w/ Papyrus and cooked with Undyne. After beating Mettaton EX, I went back to the hotel to get more healing items. Before I even entered the hotel, Undyne called for me to send the letter. Then everything else happened (true lab, Asriel boss fight) but I never fought Asgore. Instead, when he was supposed to destroy the Mercy button, Toriel hit him with fire magic. So I'm guessing that the game is slightly different on Nintendo Switch rather than on a computer. Anyway, thanks for trying to help.

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