Agar.io

Agar.io gameplay; this image shows only a small fraction of an Agar.io map. There are four cells on this screenshot. One cell is partially consuming another one. Another one of the cells is a drawing of Doge, an Internet meme.

The objective of Agar.io is to grow a cell on a Petri dish by swallowing both randomly generated pellets, known as "agar", which slightly increases a cell's mass, and smaller cells, without being swallowed by even larger cells.[4] The browser version currently holds five game modes: FFA (Free-For-All), Battle Royale, Teams, Experimental, and Party. The mobile version of the game includes Classic (like FFA), Rush Mode, and Battle Royale. The goal of the game is to obtain the largest cell; players must restart from a small cell when all their cells are eaten by larger players or fountain viruses. Players can change their cell's appearance with predefined words, phrases, symbols, or skins.[5] The more mass a cell has, the more slowly it will move.[6] Cells will gradually lose a small amount of mass over time.[7]

Viruses are green, spiky circles that split cells that consume them into many smaller cells, rendering them vulnerable and attractive targets to other players. Players can hide under viruses if their cell is small enough and their name short enough. Viruses are normally randomly generated, but players can also cause viruses to split in two by "feeding" them mass—typically in the direction of another nearby cell which the player wants to consume.[7]

Players can split their cell into two, and one of the two evenly divided cells (if the mass of the original cell is odd, one cell will be slightly bigger than the other) will be shot in the direction of the cursor when the space bar was pressed. This can be used as a ranged attack to shoot a cell in order to swallow other smaller cells or to escape an attack and move quickly around the map.[8] Split cells merge back into one cell if a bigger cell of the same player consumes it. Aside from feeding viruses, players can release a small fraction of their mass to feed other cells, an action commonly recognized as an intention to team with another player.[7]

Agar.io was praised for the addictive nature of its simple gameplay and graphics. PC Gamer included it on its list of the best browser games.[16]

Engadget described the game as "a good abstraction of the fierce survival-of-the-fittest competition that you sometimes see on the microscopic level."[17] TouchArcade praised its simplicity, strategic element, and "personality".[18] It was chosen by SFGATE as App of the Week in August 2015.[19] Criticism was mainly targeted towards its repetitiveness and the controls of the mobile version. Tom Christiansen of Gamezebo was mixed on the game, saying that there was "nothing to hold my attention" and that it was "highly repetitive, overall".[20] Pocket Gamer, reviewing the mobile version, described its controls as "floaty".[21]

Game journalists also noticed that the ability to choose usernames and skins enabled players to declare their support for geopolitical causes and figures in-game. Some even formed alliances with players supporting the same causes. Others adopted internet memes and online platforms as their skins, as well as offensive usernames.[18][22] One reviewer jokingly recounted: "I've ... seen the Earth be swallowed by Pubes, Steam absorb EA, and France split in two and flee from Mars before being eaten by Your Mom's Ass (which was, quite frankly, enormous)."[6]

In the weeks leading up to the June 2015 Turkish general election, Kotaku noticed that players using names related to Turkish politics were prevalent and often cooperated against other political parties.[5][23] An article in the journal Games and Culture argued that the feature was the main reason for Agar.io's success. It noted that Agar.io provided a platform for competing ideologies in a "survival of the fittest" simulation when they would instead be shut down on social media. In an effort to make the game more commercial, Miniclip improved moderation and removed the Swastika and ISIS skins, a move which was described as furthering the game from its original 4chan audience—Valadares himself had refused to remove the Nazi skin on Reddit.[9][10]

Because it was frequently propagated through social media and broadcast on Twitch[6] and YouTube,[24] Agar.io was a quick success. The agar.io website (for the browser version) was ranked by Alexa as one of the 1,000 most visited websites[25] and the mobile versions were downloaded more than ten million times during their first week,[26] and 113 million times as of December 2016.[27] During 2015, Agar.io was Google's most searched video game.[28] It was Google's second-most searched game in the United States in 2016.[29] A 2015 press release by Miniclip stated that Agar.io was listed as the fifth top game on YouTube's list of top games.[30]

Inspired by Agar.io's success, Steven Howse released the snake-themed Slither.io in March 2016. The game soon reached the top 10 most-downloaded apps on iOS and Android, buoyed by the similar word-of-mouth and attention from YouTubers that had propelled Agar.io. By June, Slither.io had hit over sixty million daily players.[31] It eclipsed Agar.io's popularity,[4] pushing it to second place to become the most Googled game of 2016.[32]

The rapid rise of Agar.io and Slither.io led to the beginning of a new genre of browser games, dubbed ".io games" for the domain name they use. Characterized by simple graphics and gameplay in a free-for-all multiplayer arena, .io games received around 192 million visits in 2017.[3][10][4] Many .io shooters launched after Slither.io—Valadares released Diep.io in July 2016. Miniclip also began developing new .io games.[3][33]

• In the fourth season of the television series House of Cards, the character Frank Underwood is briefly shown playing Agar.io. Underwood compares its objective of eating smaller cells to get bigger to a presidential campaign.[34]

• Valadares, Matheus (13 May 2015). "Efsane oyunun geli̇şti̇ri̇ci̇si̇ i̇le kisa bi̇r söyleşi̇ yaptik" [We had a short interview with the developer of the legendary game]. Kafakutu. Archived from the original on 15 May 2015.

• Official website