A .io Game is a genre of video game that originated in the late 2010s. These games, belonging to the MMO (massively multiplayer online) genre, are defined by having most of the following traits:
- Quick and easy to join: .io games don't require the creation of an account to play (although some do offer the option); you simply enter your username and go. They are also often browser-based, not requiring any downloads aside from the plug-in used to run the game, making them even simpler and quicker to join. Many also offer mobile apps, allowing them to be played on the go.
- Simple rules: Quite often, one can instantly deduce how to play simply by seeing the game screen. Other games show a quick tutorial to explain a few additional nuances, but it should take one less than a minute to grasp the basics.
- Player Versus Player: .io games pit you against other players, whether it be in a free-for-all or team-based competition.
- Power growth: Players grow more powerful as they play. A player's power level is often represented by his character growing larger. However, being eliminated often means losing most or all of that power.
The name of the genre is derived from the fact that many of these games' sites have the ".io" top-level domain, which was originally intended for sites related to the British Indian Ocean Territory but has since become popular with tech startups due to making a pun on input/output. In these cases, the "io" is treated as part of the game's name, with the "dot" being considered silent (Agar.io is pronounced "agario", not "agar" or "agar dot io").
The Trope Maker is Agar.io. Due to its simple yet addictive gameplay, it exploded in popularity and quickly became an internet phenomenon. Follow the Leader soon ensued when Slither.io reached similar popularity levels, and the genre was born.
Be warned that due to their simplicity and speed, the genre is notorious for being a potent Browser Narcotic. It is suggested that you stay away from this page if you need to be productive today.
Games in the genre include:
- Agar.io: The first .io game, and the first to gain widespread popularity. It is a Rising Up The Food Chain Game where players control a cell which can feed on both food particles found on the ground and smaller players, growing in size as they eat.
- Diepio: A top-down Shoot 'em Up in which players control a tank. As you earn points by destroying neutral targets and other players, you can upgrade your tank's attributes and choose from several branching evolution paths, each with unique abilities.
- Doblons.io: A top-down game where the player controls a pirate-era ship, and can upgrade it in many mutually exclusive ways by collecting the titular doblons and fighting other players.
- Flaap.io: A game that takes Flappy Bird and makes it multiplayer. Players try to get through as many pipes as possible, as the game gets faster and the bird's appearance changes.
- Goons.io: A game that has players control small creatures holding swords or other close range weapons and try to hit each other with them. Successful kills result in getting your weapon bigger until it reaches a certain length.
- Hexar.io: In this game, players control snakelike creatures that have to surround a hexagonal grid, make it their color, and make sure their trails aren't touched by other players.
- Krunker.io: Essentially a browser-based equivalent to Counter-Strike, which replaces weapon shop with several preset classes, as well as more fast-paced, arcadey gameplay.
- MassiveMatch.io: A swapping Match-Three Game where everyone plays simultaneously on the same board. Rotates between several different cooperative and team-competition modes, though they all track individual scores as well.
- MooMooio: A browser-based survival game, where the player has to gather resources and fight the animals and other players to survive in prehistoric times.
- Narwhale.io: A game in which players control a narwhal, and must skewer other players on their horn. Each kill rewards you with an upgrade to your attributes such as speed or dash cooldown.
- Pikes.io: Players control a square character holding a pike. The objective is to kill others with it, which makes it longer and easier to keep killing.
- sl4sh.io: Players control a cursor, which can perform a Dash Attack to slash other players or use a reflector shield to protect oneself. There are various classes available, and killing enemies and neutral beings or picking up energy orbs increases one's level, allowing various types of upgrades to be picked.
- Slither.io: Basically a multiplayer online version of Snake. Players control a snake which becomes bigger and longer as it feeds on energy pellets, and must avoid bumping into other players (which kills you instantly) while trying to make others run into them (which turns their body into food).
- Spinz.io: This game has players control fidget spinners that collect orbs to spin faster and kill slower opponents. Being four times as fast as your opponent will be enough to kill them instantly.
- splix.io: A multiplayer version of Qix. Players start with a small patch of land, and must capture more by drawing a closed shape over unclaimed or enemy territory, but being bumped into while outside of your home turf kills you.
- Surviv.io: A top-down battle royale inspired by Player Unknowns Battlegrounds. Around 80 players spawn on an island and must scavenge weapons and items in order to defeat all others and be the last man standing.
- Swordz.io: This game has players fight each others with swords. Getting a multiple of 100 experience will result in a level up and a longer sword.
- Wings.io: A Shoot 'em Up similar to Luftrausers: players pilot a fighter plane, and must shoot down enemy players. The plane is armed with a machine gun by default, but other weapons can be picked up including a shotgun, laser cannon, and homing missiles.
- Zlap.io: A game in which players have maces and must kill other players with them. Successful kills will make it bigger and easier to hit and defend yourself with them.
- ZombsRoyaleio: A top-down, browser-based equivalent to Fortnite. A 100 players or so disembark from a plane over an island, find loads of weapons inside crates and must kill each other until a survivor emerges, while the island is being flooded with poison gas.