Talk:Sans/@comment-26814444-20160105051304

Here is something that I noticed no one else has brought up:

When given the chance to go back and greet everyone after defeating Asriel Dreemurr, if you go back to Sans' lab, the photograph description is changed. Instead of it being a photograph of a bunch of people you don't know with Sans looking happy, it changes to a photo of you and your friends with Sans looking happy.

This is interesting because this in itself seems to be a huge time-traveling thing. Sans apparently does have the photo at the end of the pacifist run when you leave, and he keeps it in his lab. How he got it, I don't know, but it surprised me when it happened.