1, in which PE needs one person not to kill.
2.NE needs to kill more than one person, but it can't kill them all (boss can, Du Yuesheng can, and different monsters will lead to different dialogues in the corridor trial).
Ge needs to kill all monsters, defeat the judges, and finally sell his soul (this line of customs clearance will become black history and have a peaceful and perfect ending).
Extended data:
Undertale is a role-playing story game. The background of the game is that a long time ago, the earth was ruled equally by two races, namely humans and monsters. One day, the drums shattered the peace between the two sides; Under the aggression of near-slaughter, mankind has won great victories. Humans banished the monster to the underground world, and seven wizards set up a rather powerful magic barrier to trap the monster in the underground world.
People can enter the lower bound at Mount Ebert, but they need at least a human soul and a monster soul to leave the lower bound. Before the story began, no one left the lower bound alive, which led to rumors that the climbers on Mount Albert had left and never came back.
The monster is trapped in the underground world and ruled by Asgard Drummond. After the monster dies, the body will immediately turn to ashes, without soul and body. Monsters' souls are far less powerful than human beings.
Reference: Baidu Encyclopedia -undertale