The participants of the Killing Game were fifteen members of the Remnants of Despair, and an observer from the Future Foundation. The killing game took place inside a virtual world known as the Neo World Program, which resembles Jabberwock Island.
The Neo World Program's original purpose was to remove the brainwashing effect on the fifteen students, until Izuru Kamukura uploaded an AI version of Junko Enoshima, which messed up the entire program and started the killing game.
Although Izuru was labeled as a Remnant of Despair, he was never brainwashed into committing despair-inducing acts. He took an interest in despair for its unpredictability after he was persuaded by Junko to take part in the first killing game. Later on, however, Izuru bore witness to another event which served as evidence of how unpredictable hope can be. Ultimately, he remained undecided between hope and despair, and thus merely spent his tenure as a member of Ultimate Despair in order to witness Junko's despair while looking for an opportunity to pit hope and despair against each other.
After Junko's death, Izuru convinced the other Remnants of Despair to participate in a new plan: allow the Future Foundation to capture them and put them in the Neo World Program, an advanced computer simulation intended to purge the brainwashing that had driven them to despair. Izuru then started to upload an AI version of Junko into the program, corrupting it and forcing the Remnants to take part in a killing game. Their plan was to make the Junko AI inhabit their bodies by "killing" them in the simulation, effectively reviving their leader several times over. However, Izuru's true aim was to set up a battle between hope and despair, allowing him to choose which side to take once and for all.
Like the Killing School Life, the Killing School Trip is a killing game where the students are forced to murder each other in order to escape. After a muder has taken place, the students must work together to investigate and reveal the culprit, dubbed as the "blackened". After a period of time investigating, Monokuma will initiate a class trial, where the remaining students present their arguments in a courtroom and try to find out who the blackened is among them. Once the students decide on a conclusion, Monokuma will start the "voting time", where the students vote on the identity of a blackened. If the majority of the students' votes are wrong, then the blackened can get out of the school, while the remaining students get executed. However, if the majority of the students choose correctly, then the blackened alone will be executed and the remaining students will remain unharmed.
List of Rules
- Usami's rules:
- Rule #1: Extreme violence is prohibited on this island. Please live peaceful and relaxing lives with your fellow students.
- Rule #2: Be considerate of each other and work together to obtain Hope Fragments.
- Rule #3: Littering is not allowed. Let us coexist with this island's bountiful nature in "mutual prosperity".
- Rule #4: The lead teacher cannot directly interfere with the students. An exception to this rule is made if any student violates a rule.
- Monokuma's rules:
- Rule #5: Once a murder takes place, a class trial will begin shortly thereafter. Participation is mandatory for all surviving students.
- Rule #6: If the blackened is exposed during the class trial, they alone will be executed.
- Rule #7: If the blackened is not exposed, the remaining students will be executed.
- Rule #8: As a reward, the surviving blackened will be forgiven of their crime and allowed to leave the island.
- Rule #9: The Body Discovery Announcement will play as soon as three or more people discover a body for the first time.
- Rule #10: Destroying any property of this island without permission is expressly prohibited. This includes the surveillance cameras and monitors.
- Rule #11: You are free to investigate this island at your own discretion. Your actions in this regard are not limited.
- Last Rule: Additional School Trip Rules may be added at the headmaster's discretion.
- The following rule was added later:
- Rule #12: The blackened may only kill a maximum of two people during any single "killing game".
Similar to the previous killing games, Monokuma decided to make motives in order to escalate the students' desire to kill each other.
- Motive #1: Lost Memories
- Monokuma revealed to the students that Monomi had stolen their memories of attending school at Hope’s Peak and promised to restore their memories if they killed.
- Motive #2: Twilight Syndrome Murder Case
- Motive #3: Despair Disease
- Several students were afflicted with a disease that caused them to exhibit behavior opposite to how they usually act.
- Motive #4: Starvation in the Funhouse
- The students were trapped in the Funhouse without access to food, and would only be released if a murder was committed.
Results and Aftermath
Ten out of fifteen Remnants of Despair remained comatose in the immediate aftermath, and the other five opted to stay on Jabberwock Island until they could find a way to help them. A peacekeeping squad was dispatched by Kyosuke Munakata to Jabberwock Island to kill the survivors, but Byakuya Togami's own squad saved them and presumably transported all the inhabitants off of the island.
Sometime during the Final Killing Game, all of the comatose victims of the Killing School Trip were awakened from their comas by Izuru. Purged of their previous brainwashing, they joined their remaining friends in rescuing the Future Foundation and stopping Ryota Mitarai from brainwashing the world. After taking the blame for the Final Killing Game, the whole class (including Ryota) decides to return back to Jabberwock Island.