The difference between the triangle rune violence line and the peace line

Carnage line: Chara appears at the end and ends the game, reminding you that you should fight for a better ending.

Peace Line: No one, because this is the best ending and no explanation is needed.

Neutral Line: Sans appears in various neutral lines. At the end of the game, he will tell you what happened underground because of your choices.

Hypocrisy line: No one, because this is the best ending and no explanation is needed. This variable only exists because you have fought the massacre line, but the ending is the same. There should not be an extra line, it is the peace line.

So why can Chara and Sans talk to players and realize the difference in the ending of the game?

Why is there a variable for hypocrisy?

This is very simple, because the game has an evil archive system. It was precisely because of this that the timeline changed, and Xiaohua, Chara, and Sans felt the energy of reset. It's unclear why this perception ability was obtained, but it should be related to the creator of the archive. I guess it is Gaster, but there is no basis for it.

Then the truth is revealed. It is precisely because of the archive system that UT has different endings, and the definers of these endings are characters who can sense archives and talk to players.