Aradia: Finished and won the True Pacifist run, refuses to touch the game again because everyone’s happy (and also she very heavily relates to Sans)
Tavros: Can’t handle the pressure of playing the game himself, watches playthroughs on Youtube and lowkey feels guilty about it
Sollux: Plays several neutral runs, then the True Pacifist run, then the No Mercy run, because he wants to play through every possible outcome
Karkat: Killed Toriel because he thought he had to, started acting as a pacifist once he got to Papyrus and was genuinely touched by his words
Nepeta: Played as a Neutral Pacifist up until she got to Temmie Town, then she rebooted the entire game and went No Mercy out of anger and spite
Kanaya: Her computer is so full of viruses up that she can’t download the game, so she just watches her friends play it
Terezi: Went a partial-Pacifist Neutral route until encountering Undyne, then she reset the game to go True Pacifist because she wanted to be Undyne’s friend
Vriska: Tried to go the No Mercy route, but gave up around after she couldn’t defeat Undyne the Undying after like 100 tries
Equius: Played as a True Pacifist up until he encountered Aaron, he became too nervous to keep on playing after that point
Gamzee: Won as a True Pacifist, and watches a playthrough of a No Mercy run with Tavros, is sobbing by the time Toriel dies
Eridan: Does No Mercy first, then the True Pacifist run (he screams at what happens at the end)
Feferi: Played No Mercy only because she really wanted to fight Sans