To date, "Surgeon Simulator" has sold over 2 million copies. Those aren't bad numbers for a game that was initially developed in less than 48 hours (though, to be sure, Bossa has spent the next year and a half improving "Surgeon Simulator" and taking it to other platforms).
The developer's latest title, "I Am Bread," seems to be following a similar route. It racked up over 34 million YouTube views in December and is on a similar sales trajectory as its predecessor.
While YouTube has been a key factor in the company's success, the company says that's never a consideration when coming up with game designs.
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"If you try to target YouTubers, you're approaching it wrong," says Luke Williams, lead designer of "I Am Bread." "At the end of the day, if the game isn't fun and doesn't have engaging mechanics, then [players] aren't going to have fun with it and not view videos. It's safer to just ignore this phenomenon."
Smaller, independent games aren't the only ones who are benefiting from the rise of YouTube as a viral marketing platform. Major video game publishers are also seeing increased awareness of their games because of it, although they note it's just a piece of the puzzle and doesn't replace outreach to traditional media or other forms of marketing.
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"YouTube is pretty diverse," says Pete Hines, vice president of marketing at Bethesda Softworks. "It's one way to get stuff directly to fans and in front of the consumer and do it in a way that is not us speaking but giving folks a chance to hear from other people."
Big publishers are nonetheless making sure to get AAA games into YouTuber hands early, often prior to their initial on-sale date to maximize exposure to a large and growing audience. Ultimately, though, it's independent games that have benefited most from the social media service, though. Titles like "Minecraft" have a rabid following, with several of the top YouTube stars focusing on it.
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Like "Surgeon Simulator," "Minecraft" started as a small title that was struggling to compete against big studio releases. Ultimately, of course, it outsold many of them. Life to date, developer Mojang has sold over 50 million copies, and the company was purchased by Microsoft last September for $2.5 billion.
Bossa's Olifieres has a theory on why Indie games are such a favorite focal area on YouTube. While players may seek out tutorials of larger games, he says, they prefer to talk about experimental and quirky titles, which tend to be what indie developers specialize in.
"Because it's original, it lends itself to be talked about," he says. "You can't define these sorts of games, and that's a talking point."