Full battle here: https://www.youtube.com/watch?v=9bo3w3Ju_fI
Whenever you get killed by Sans and come back to fight him later, he makes a comment about your total deaths up until a certain point
There are two pieces of dialogue that I missed, which you get when you defeat him, reset the game and then fight him again:
"..."
"that expression that you're wearing..."
"..."
"well, i won't grace it with a description."
Doing this twice:
"..."
"that expression that you're wearing"
"..."
"you're really kind of a freak, huh?"
#Sans #Undertale