Survival Game

The Survival Game is the Battle Royale tournament hosted by Deus Ex Machina in order to choose his successor as the God of Time and Space. Twelve individuals were selected as participants, although one candidate consists of two people (Marco Ikusaba and Ai Mikami). Deus initiates the game on April, 2006. Each of the candidates are given the Future Diaries to use to predict their futures. The last man standing will become Deus' successor, while the others must be killed or their diaries destroyed to eliminate them from the tournament. Deus acts as the judge, with his assistant Muru Muru handing out the diaries and acting as his secondary judge. Two survival games in alternate worlds took place, the first won by Yuno Gasai and the second won by Yukiteru Amano, although the rules of the second game were altered by Deus himself, allowing Minene Uryu to survive the second game.

Game Overview
The survival game has several rules which are vital to the diary owners and the game's progress:
 * All diaries predict the future in different ways.
 * Each owner is assigned a number from one to twelve and are referred to by their titles (e.g. "First"). Until their true identities are discovered through the diaries, the owners are referred to by their titles.
 * The futures of the diaries are not set in stone. If a diary owner or another person does an action that contradicts the entries on the diaries, then the future will change accordingly.
 * The diaries literally carry a person's future. If they are broken, then the diary owner will be erased through existence and removed from the game.
 * No diary owners are allowed to quit or retire from the game, although giving the diary temporarily to a third party is acceptable.
 * The game will officially end when only one diary owner is left alive. The winner shall become God.
 * Deus and Muru Muru must not interfere with the actions of the game. Both characters break this rule during the second game.

The official timeline takes place between April and July, ending on July 28th. Contradictory dates between the manga and anime make the starting date for the game difficult, but it is likely between April 21st and April 24th, on the day after Yuki receives his Future Diary from Deus. It appears that Muru Muru handed out the diaries to the diary owners in a random or reversed order, Yuki being the last one to gain his.

Occasionally, Deus holds meetings between the diary owners to monitor their progress and for the owners to ask him questions regarding the game. These meetings take place in the Cathedral of Causality.

Participants
Deus and Muru Muru act as the judges of the survival game, Muru Muru taking over Deus' role with his death to ensure the throne of god is filled. It is revealed that there is a third judge called the Observer, an artificial human designed to secretly observe the game from within. The Observer is actually Aru Akise.

There are technically thirteen diary owners although two are counted as one. The diary owners are:
 * 1) Yukiteru Amano - The First diary owner. A 14-year old middle-school student. He has the "Random Diary".
 * 2) Yuno Gasai - The Second diary owner. Another middle-school student, and Yukiteru's personal stalker. She has the "Yukiteru Diary".
 * 3) Takao Hiyama - The Third diary owner. A teacher who moonlights as a serial killer. He has the "Murder Diary".
 * 4) Keigo Kurusu - The Fourth diary owner. Chief inspector of Sakurami City's police force. He has the "Criminal Investigation Diary".
 * 5) Reisuke Houjou - The Fifth diary owner. A 5-year old toddler with genius intellect. He has the "Hyper Vision Diary".
 * 6) Tsubaki Kasugano - The Sixth diary owner. The priestess of the Omekata religious order. She has the "Clairvoyance Diary".
 * 7) Marco Ikusaba and Ai Mikami - The Seventh diary owners. A pair of lovers who are connected to the Mother's Village orphanage. They share the "Exchange Diary".
 * 8) Kamado Ueshita - The Eighth diary owner. Director and headworker of the Mother's Village orphanage. She has the "Blog Diary".
 * 9) Minene Uryu - The Ninth diary owner. A terrorist who targets religious organizations and structures. She has the "Escape Diary".
 * 10) Karyuudo Tsukishima - The Tenth diary owner. A dog breeder and owner of a dog care home. He has the "Breeder Diary".
 * 11) John Balks - The Eleventh diary owner. The Mayor of Sakurami City, and co-creator of the diaries. He has the "Watcher Diary".
 * 12) Yomotsu Hirasaka - The Twelfth diary owner. A blind vigilante. He has the "Justice Diary".

The First Survival Game
The first game occured when John Balks approached Deus with the proposal to help evolve humanity by giving them some of his power. Deus, knowing his own death was approaching, agreed and the two created the first Future Diaries. Deus decided to create the survival game to decide on a successor to his throne and title.

Choosing twelve individuals who all had diaries, Deus created Future Diaries for them and had Muru Muru hand out each diary owner to the chosen twelve. Minene gained hers when fleeing from the police after a failed attempt to murder a cardinal, falling out of a high story window and was saved by Deus when she agreed to play the game. Muru Muru visited Yomotsu in his secluded log cabin where he lamented on his inability to perform justice and received his diary. Reisuke Houjou needed convincing to participate in the game, Muru Muru having to pretend that she was an alien in order to convince Reisuke the Future Diaries told the future. Tsubaki Kasugano gains hers after Muru Muru spends a day hanging out in her isolation room. Keigo Kurusu gains his from Muru Muru when they spend time together at a café. Takao Hiyama gained his from Muru Muru after killing someone, but due to his paranoid attitude, he ended up destroying his diary twice until he realised what was going on. Yuki personally gained his from Deus, believing he and Muru Muru were his imaginary friends.

Details on the survival game are vague, but Yuki, Yuno and Kurusu formed an alliance to locate the other diary owners. Eventually, the trio became the last surviving members of the game. Kurusu ended the alliance when he learnt his son was going to die from a terminal heart disease, but he was eliminated. Unwilling to kill each other, Yuki and Yuno decided to commit a lover's suicide. They both took lethal drugs and seemingly died together. However, Yuno faked her death by not swallowing the drugs in order to become God. But upon becoming God, Yuno realised she could not resurrect Yuki, impossible even for a god, and went insane. Muru Muru suggested she perform a time leap back in time, creating a parallel world where she could reunite with her beloved Yuki and start a second game. Yuno complied, leading to the second survival game. Yuno murdered the alternate version of herself, and Muru Muru imprisoned her second self in Yuno's Illusion World, and gave Yuno a second Future Diary to give her a better chance of winning the second game.

Order of Elimination
The order of eliminated diary owners is revealed in the anime's first opening "Blood Teller":
 * 1) Takao Hiyama - His diary was broken by Yuki and Yuno.
 * 2) Yomotsu Hirasaka - Shown being stabbed by Yuno in the anime's twenty-third episode.
 * 3) Reisuke Houjou - Shown being strangled by Yuno in the anime's twenty-third episode.
 * 4) Tsubaki Kasugano
 * 5) Marco Ikusaba and Ai Mikami
 * 6) Kamado Ueshita
 * 7) Karyuudo Tsukishima
 * 8) Minene Uryu
 * 9) John Balks - Implied to have been killed by Yuno due to events in the second game.
 * 10) Keigo Kurusu - Broke the alliance to become God, and was overpowered by Yuki and Yuno.
 * 11) Yukiteru Amano - Committed suicide with Yuno, but she faked her death.

Order of Elimination
The order of elimination for the second game was likely altered from the original, after Yuki retconned the game's planned future by discovering the second Yuno Gasai's body in Yuno's house. The order of elimination is as follows:


 * 1) Takao Hiyama - His diary is pierced by a throwing dart thrown by Yuki.


 * 1) Yomotsu Hirasaka - Throat slashed by Yuno.


 * 1) Tsubaki Kasugano - Her diary is pierced by a throwing dart thrown by Yuki.


 * 1) Reisuke Houjou - He is stabbed in the chest with a knife by Yuno.


 * 1) Karyuudo Tsukishima - He is shot in the back of the head by Keigo Kurusu.


 * 1) Keigo Kurusu - After ending his alliance with Yuki and Yuno early due to Muru Muru's manipulations, Kurusu killed Tsukishima and tried to murder Yuki and Yuno. Shot by Yuki, Kurusu tries to kill Yuno but is confronted by Minene and fellow policeman Masumi Nishijima, learning because he committed a crime, he is no longer a policeman and his diary is useless. Kurusu eliminates himself from the game by breaking his diary.
 * 2) Marco Ikusaba and Ai Mikami - Ai's throat is slashed by Yuno and she dies from blood loss. Marco dies when the Sakurami Tower collapses.
 * 3) Minene Uryu - After losing an arm to a claymore bomb, and being shot by Yuki, Minene sacrifices herself by trying to blow the safe doors off the bank vault John Balks is hiding in. Destroying her phone, Minene seemingly dies when a bomb activated by her heart stopping explodes. However, she survives, given a portion of Deus' powers by the dying god to interfere with Muru Muru's manipulations. Because of this, she's no longer an official participant.
 * 4) John Balks - Decapitated by Yuno. He is shot in the head in the anime.
 * 5) Kamado Ueshita - After witnessing Yuki kill his friends Hinata Hino, Mao Nonosaka and Ouji Kosaka, Kamado accepts her inevitable death and is stabbed by Yuno.
 * 6) Yuno Gasai - After travelling to a third parallel world to repeat the game, Yuno realises there is no point after realising Yuki altered the future to ensure her third self has a happy life. She stabs herself with a knife to let Yuki survive, refusing to kill him. However, Muru Muru manages to salvage her memories and put them into the third Yuno, technically letting her survive.

A third game was attempted by Yuno and Muru Muru, but due to their own alterations to the future, John Balks learns of his future death and cancels his development of the Future Diaries, cancelling out the survival game. With Yuno's suicide, Yuki becomes the winner, although with Minene possessing a portion of Deus' powers, and Yuno's memories and powers being diverted to the third Yuno later becoming a deity as well. Therefore the second game can be seen as ending with three winners.