Darwin's Game is about a mysterious mobile game that turns players into a kill-or-be-killed battle royale: 

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• Premise

  {{User}} accepts an online invitation to play a mysterious game called Darwin's Game. The game is a fight to the death where players are given a Sigil, an evolutionary ability that varies from player to player. Players can die in the game and in real life. 

• Gameplay

  The majority of the series revolves around a 24-hour minigame where players collect rings and solve a puzzle. Players can kill each other to take rings, or work together. 

• Characters

  Each Character and Player has a different motive for entering the game, and a different motive for continuing to participate. Some characters are apex predators who enjoy winning, while others prefer to run away and hide. 

• Game Master

  It's later revealed that the Game Master is one of many in the multiverse and is actually benevolent.

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Here are some rules of the game in the anime Darwin's Game:

Sigils:

Players are given a Sigil, which is an ability that varies from player to player. For example, Sense Expansion type Sigils can strengthen a player's five senses or give them a sixth sense.

A Sigil (シギル) is an ability all players taking part in the Darwin's Game possess, granted once they join the game.

Information:

Not much is known about sigils other than they are otherworldly superhuman abilities granted to players of the Darwin's Game with each and every player who takes part in the game receiving a randomized and unique sigil immediately upon creating an account. Players automatically know how to use their sigil and it's impossible to change your sigil once gained.

There's four ranks to sigils and lists their percentages along with her own reasoning on the naming rules: 75% are "Animal Rank" sigils that have an animal's name, either transforming the user's body or expanding their five senses; less than 20% are "Superhuman Rank" sigils whose names are based on the function of the sigil, many of these are unique; less than 4% are "King Rank" sigils that have the kanji of royalty in them and are mostly powerful telekinetic types; and finally, less than 1% are the extremely rare "Myth Class" sigils that are named after gods.

People from Japan in World Line O refer to sigils as Koujinryoku (荒神力) and only officers of the imperial guard have been shown to use it so far. It's also been stated that the imperial family is apparently monopolizing the koujinryoku and there are those that don't like it as they believe sharing it to everyone would result in equality. Those people are later revealed to be agents of the Great Russian Republic who refer to sigils as Exen (エクセン).

Types:-

Telekinetic:

Telekinetic (念動系) type sigils give the user the power to manipulate specific materials or items, which range from the user's own body, other people, or simple inanimate objects. Examples of this type include Karino Shuka's Queen of Thorn and Wang's Beelzebub.

Metamorphic:

Metamorphic (身体変化系) type sigils can either completely or partially change the user's body into a totally different quality or shape from their original form. Examples of this type include Danjou's Wall Iron and Hiiragi Suzune's Mag Mell.

Mind Control:

Mind Control (精神操作系) type sigils are capable of directly influencing the mind of a target; imposing thoughts, actions, and/or demands upon the subject, though some only work on humans and specific animals. Examples of this type include Ayanokouji Kaito's Peace Maker and Themis' Unbalance.

Scientific Engineering:

Scientific Engineering (科学錬成系) type sigils allow the user to create specific chemical substances for various uses. An example of this type is Amagasa's Asclepius.

Sense Expansion:

Sense Expansion (感覚拡張系) type sigils either strengthens the user's five senses or bestows them with a unique form of sixth sense and because of this they're also referred to as "ESP types". Examples of this type include Maesaka Ryuuji's True or Lie and Kashiwagi Rein's Laplace.

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Battle length:

Battles last for an hour. If the battle is not decided by the end of the time limit, the winner is determined by the players' damage, technique, and artistry.

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Battle types:

There are four types of battles:

-Rank battle: A one-on-one battle

-Clan battle: Two clans fight against each other

-Flag game: Clans buy a clan flag from a store to claim land and defend it for 30 minutes

-Darwin's Game event: Takes place under special rules.

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Death:

Players who refuse to play, quit, or defy a command face death after 24 hours.