Agar.io

The objective of Agar.io is to grow a cell on a Petri dish by swallowing both randomly generated cells, known as "agar", which slightly increases a cell's mass, and other smaller cells (players), without being swallowed by even larger cells. The more mass a cell has, the more slowly it will move. Cells will gradually lose a small amount of mass over time. 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. Consuming a virus will change your mass by +100 and red viruses change your mass by +200. 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. ==History==

Development Agar.io was created by nineteen-year-old Brazilian developer Matheus Valadares, written in JavaScript and C++. Valadares shared an IP address to the game for playtesting on the 4chan video game board /v/ and game development forums, before releasing it on the domain agar.io on 28 April 2015. It is named after agar, a substance used to grow cell cultures. Valadares continued to experiment with adding new featuresexperimental mode was created specifically for this purpose. He thought about adding more complex biological features like photosynthesis and mitochondria, but ultimately decided to strip the game down to its current simple mechanics. In-game advertisements covered server costs. Popularity Valadares never marketed Agar.io outside of his single post on 4chan, where he received feedback and users formed "cartels" to get on the in-game leaderboard. Dedicated Agar.io YouTubers saw their subscriber counts quickly rise. Commentators also suggested Agar.io's accessibility as a free browser game, as well as the addictiveness of its simple and intuitive mechanics, as reasons for its unexpected success. ==Reception==

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. Engadget described the game as "a good abstraction of the fierce survival-of-the-fittest competition that you sometimes see on the microscopic level." TouchArcade praised its simplicity, strategic element, and "personality". It was chosen by SFGATE as App of the Week in August 2015. 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". Pocket Gamer, reviewing the mobile version, described its controls as "floaty". 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. 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)." 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 audienceValadares himself had refused to remove the Nazi skin on Reddit. 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 and the mobile versions were downloaded more than ten million times during their first week, and 113 million times as of December 2016. During 2015, Agar.io was Google's most searched video game. It was Google's second-most searched game in the United States in 2016. A 2015 press release by Miniclip stated that Agar.io was listed as the fifth top game on YouTube's list of top games. ==Similar ".io" games==

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. It eclipsed Agar.io's popularity, pushing it to second place to become the most Googled game of 2016. 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, .io. Characterized by simple graphics and gameplay in a free-for-all multiplayer arena, .io games received around 192 million visits in 2017. The large number of such games led to the fragmentation of the user base, with too many games and not enough human players. This led to the implementation of video game bots within the servers of the game. Essentially, the purpose of the bots was to keep the lobbies full, which would increase the chances of having real players remain within the game. This raised ethical concerns, especially because game developers were not making clear that the players were competing against artificial intelligence within the game, damaging its social experience. This was not the case with Agar.io alone: Hole.io was also suspected of having bots within the arena. Players were able to prove this by turning off the internet during the middle of the game, and the game was able to continue without interruption. ==Notes==