An unlikely internet sensation when it launched in 2015, Agar.io spawned an entire genre of spinoff “-io” games with trademark low-res graphics and free, free-for-all gameplay. Nowadays, its popularity has mostly been overtaken by Slither.io, but Agar.io still has a core fanbase that has stuck around over the past half-decade and more. Whether you want to jump back into the game for nostalgia’s sake or try it for the first time, be warned: You’re going up against cell-devouring veterans who will chew you up and spit you out, literally and figuratively.
We’ve collected all of the techniques you’ll need to get your start in Agar.io and master it.
While you can choose to play as a guest online, the game incentivizes signing in via Facebook or Google by unlocking saved progress, a larger starting mass, daily quests, free coins per hour for the shop, gifts, leaderboards, and special skins.
That said, if you want to just dive right in for a few rounds and don’t care about saving your statistics, you don’t need any of these. You can hop on without any perks and still reach the top of the leaderboard. You’re just starting at a disadvantage and don’t get any credit in-game for playing well.
Before you hit Play, enter your name (or any name), and it will appear in the middle of your cell when the game starts. You can also enter certain names that will give your cell a unique skin, or appearance. For example, entering your name as “Earth” will make your cell look like the planet, “France” will add French flag colorings, and certain politician names will plaster their face into your cell. You can find an updated list of all the free available skins at this site.
If you win as a default skin name, your leaderboard climbs won’t stand out from all the other players with set names. To use your own username without getting stuck with a boring monochrome cell, you’ll have to log in to an account so you can draw your own skin pattern — or, earn coins to buy premium patterns in the Store.
Choose your mode
There are five game modes to pick from: Free-for-all (FFA), Battle Royale, Teams, Experimental, and Party Mode. The latter mode allows you to avoid strangers altogether and make a private server for you and your friends.
FFA is endless, so you never win per se. You can rise to the top of the in-game leaderboard, but eventually, you’ll be overtaken, eaten, and have to start over. It’s a good choice to start with while you master controls. Unfortunately, it’s not always truly free-for-all, as players from particular countries or clans will team up with one another, feeding each other so that you can never catch up naturally on your own.
Battle Royale has the same contracting safe zone as most battle royale games and also starts when a set number of players are in the lobby. Unlike in FFA, where you’ll always start as the smallest cell, everyone starts on an even playing field, and the shrinking safe zone keeps games down to just five minutes or so apiece.
Teams avoid the problem of unofficially aligned players by putting everyone on opposite sides. You’ll partner up with strangers, and the most skilled group will overwhelm their opponents. Experimental, meanwhile, is where the game designers put in silly rule changes that switch up the gameplay from the core modes. It’s a fun change of pace but usually will have fewer players in a given server.
Controlling your cell
Once you’ve entered the game, the controls for Agar.io are simple:
- Move the mouse to move your blob. Your cell will automatically move toward your mouse cursor.
- Press the Space Bar to split your cell or cells in two.
- Press W to eject mass.
In the beginning, you are a tiny cell sitting in a vast expanse. As you move your mouse around or tap on your screen, your cell will automatically move toward your mouse cursor or taps. The game area is dotted with tiny, colored pellets. When your cell runs into pellets, it will consume them and grow larger. Eating pellets will also increase your score.
Agar.io is also a multiplayer game, meaning you’ll quickly run across other players as you move around. Run into smaller character cells, and you’ll subsume them into your mass, but let a larger cell gobble you, and you have to restart the game. If a cell looks like it’s just smaller than you, avoid it, as a cell must be 90% of your size or less in order to be consumable.
As you consume more and grow larger, you’ll climb up the leaderboard, but you’ll move more slowly, making it harder to catch vulnerable, smaller players. You can try to trap them against the edge of the map or between another large cell, but for the best results, you’ll need to use more advanced techniques.
Strategic splitting and ejecting
Spend too long as a large bubble, and other players could expand into even larger behemoths while you’re puttering around, too slow to catch anyone. That’s why Agar.io players split themselves in two by pressing the Space button. While it makes you more vulnerable to large opponents, it also makes it easier to catch smaller prey or to simply collect stray pellets at a faster pace. Once you’re split, your bubbles will move in unison and will recombine into one unit after a minute or so.
An alternative option is to hit W to eject a smaller pellet of mass. Unlike the space bar, which automatically breaks you in half, the pellet won’t steal too much of your mass but can still be useful. A smaller you can more easily catch up to your prey, lingering tantalizingly just out of reach. Just make sure that you don’t feed pellets directly to other players, who will automatically eat them and grow in size, while you’ve just lost some mass.
The eject option is also great as a last-minute escape attempt. If you know you’re close to being eaten, you can expel some mass to gain some quick speed, luring your hunter away to eat the free pellets while you live to feast on pellets another day. It’s also the only way to communicate. Shooting a pellet can be a way of saying hello, thanks, or even “let’s collaborate.”
Avoid viruses and microtransactions
Scattered around the play area are large green blobs covered in spikes. These are viruses. They do not move, and eating them is … inadvisable. If you are larger than a virus, consuming it will cause your cell to split into many smaller cells. Yes, you’ll grow from the mass you’ve consumed, but nine or 10 parts of you are tough to shield from other players. As such, viruses present a hazard to large cells and a sort of safe haven for smaller ones. If being pursued by a larger cell, you can take shelter behind a virus. Large players will often be wary of risking a split, especially if there are other players nearby who can gobble them up.
We also recommend you don’t spend your money on custom skins or boosts. $10 only translates to 7,000 coins, which will buy you only a single premium skin depending on the rarity of the design. You’ll earn coins simply by playing well, so choose a skin or two that appeal to you, and then treat them as a reward for eating lots of your competitors.
Take on the world
Unique game modes aside, the core of the gameplay hasn’t changed in all this time, with the exception of pay-to-win additions by the developers. But it didn’t have to. Playing Agar.io taps into the most basic elements of competition. Eating another player evokes a primal glee, like a lion must feel crashing down on the back of an antelope. Death comes quickly in Agar.io, but it’s easy to bounce back straight into the action. With quick reflexes and a Machiavellian appetite, you might survive a while.