A Browser Game Called Agar.io Got Googled More In 2015 Than 'Fallout 4'

It's just another day in the petri dish. I've collected enough free-floating mass that soon, if I want to keep growing my cell, I'll need to start hunting other players. Suddenly, I spot some larger blobs in the corner of my screen.

"Free food," I think to myself. "Nice."

I use my mouse to bear down on the blobs, but it's already too late—they were a trap set by a sprawling complex of green blobs, each far larger than I, all controlled by the same savvy player. He or she splits each of the green blobs in half, springing the new ones toward me and devouring me whole.

This is Agar.io, an explosively popular browser-based game that you've probably never heard of. If you did, chances are it was when Google released the most-searched terms of 2015: "Agar.io" was in seventh place—behind "Ronda Rousey" and "Paris," but ahead of "Fallout 4." Earlier this year, two separate political parties in Turkey riffed on the game in political ads.

The mechanics of Agar.io (the title is apparently derived from "agar," a substance used to grow cultures in Petri dishes) are infuriatingly simple. You start as a tiny cell, which you control with your mouse, but the more mass you consume, the larger you grow. At a certain point, you might start trying to consume your fellow players, either by cornering them or splitting yourself in half for a predatory inertia boost. Or, like the green blob who ate me, you can eject smaller blobs that you no longer control, either to lay traps or to manipulate non-player "viruses" into splitting up larger cells.

There isn't even have an explicit goal. Many players try to get as large as possible, or at least onto the top 10 leaderboard. Others cruise the map at a moderate size, trying to kill the largest players. Some spend the entire time feeding, in successive final acts of either charity or incompetence, depending on your perspective.

Oh, and there's no chat function, so the only way to communicate is using your player name. "Help me" is a common moniker; others range from in-jokes to unprintable racial and sexual epithets. Complicating things further is that choosing the names of certain memes and geopolitical entities—"Trump," "North Korea," "9gag," etc—gives your cell an MS Paint-style skin. The result, at least in my mind, is that the game feels like an endless, weirdly-literal battle of ideas—a sort of competitive memescape where allyship are enmity are snap judgments based on the thinnest and most flexible claims of identity.

I have to admit, though, that when I find a cell with a particularly hateful name, I usually try to splitkill it.

If none of this makes sense, you should probably just play a round or two (there's no account required). If you're anything like me, you'll emerge in five or six hours, bleary-eyed and angry. If Agar.io itself can be believed—a tall order, perhaps, given its impish sense of humor—we'll both be in good company; on any given day, it's not unusual for the game to report that hundreds of thousands of players are online across the world.

The creator of Agar.io, a Brazilian student named Matheus Valadares, sold the game to the gaming site Miniclip earlier this year.

"When we saw Agar.io's rapid rise in popularity in its early days, and subsequently all started playing it in the office, we knew it was something we'd love to be a part of," said Miniclip CEO Rob Small. "We saw huge potential."

Last summer, before he sold the game, I tracked down Valadares, who now works for Miniclip on the Agar.io develop team.

"I didn't really do any marketing," he said of the game's early days. "I only shared it once on 4chan and that was it."

All of Valadares' initial feedback on the game, actually, ended up coming from 4chan, which seized on the game and gave it its first popularity boost, with some players using the image board to form massive cartels in order to climb the leaderboard.

The game was originally supposed to be more complex, incorporating biological processes like mitochondria and photosynthesis. In the end, though, Valadares said that he stripped the game down to the essentials that remain online today.

Agar.io wasn't his first game, he said. Others he's made include a similarly-addicting multiplayer version of Flappy Bird called FlappMMO and a weird, cursor-based one called Cursors.io.

Valadares seemed either bored or distracted during our interview, but he did answer a few of my most pressing questions. He never expected the game to become as large as it did, he said. He drew the cell skins himself.

He was elusive about his future plans for Agar.io—probably, in retrospect, because he was preparing to sell it—but at the time, he said, in-game ads were already covering server expenses.

I also asked him what Agar.io was really about. Do the cells in the game represent actual biological cells? Or memes? Or is it totally abstract?

"Cells and dank memes," he replied, without explaining further.