Over 5 million people have signed up to Path of Exile. "Roughly" 1.2 million people are expected to play its next expansion during the month of its release, Chris Wilson, managing director of Grinding Gear Games, its developer, tells Gamasutra. The game -- a Diablo-esque dungeon crawler -- is completely free-to-play. Its microtransactions are entirely cosmetic and have no effect on the gameplay -- and its gameplay is tuned like a premium game, with no stopgaps or gates. Yet its developers are wildly successful. How does that work?

Building a Community, Building Hype

Path of Exile was in development for seven years before it was released -- and for four of those, Grinding Gear Games did no press at all. Even when it began to reach out to journalists, the New Zealand-based team had little budget for promotion and few connections, and the game flew in under the radar. That didn't stop Wilson from pushing forward with his own community efforts -- which he is still directly hands-on with. "I like to handle it myself, to make sure the message is consistent with our company values and also because I really enjoy talking to our community," he says. He posts on the game's forums, its blog, and also on Reddit. Over the years, he has published "constant news updates" to the game's website, and made sure to publicize any and all announcements the team would make about the game. "We incrementally built the size of the community over time by essentially just keeping at it," Wilson says. It's not the case that the game has ever had a spike in signups, he says, but a slow constant upward trajectory -- "building on what had come before," says Wilson.

From Crowdfunding to "Supporter Packs"

What has driven Path of Exile's success is its monetization model -- which is quite different than many other free-to-play games. It evolved naturally over time, Wilson explains. There are no gates or delay mechanisms, and no pay-to-win mechanics. All microtransaction items are purely cosmetic -- a style that's often said not to play well with Western gamers despite its popularity in Asia. It's the "supporter packs" that the company sells which have driven player interest in that, says Wilson. When the game went into its first closed beta, the community had been building for some time. The studio had decided to give out a very limited number of beta keys: no more than 100 per day, when the community already had hundreds of thousands of registered users. Prospective players started to "beg" the team to sell access to the game, Wilson says. "We didn't like the idea at first," he says, so the team did a crowdfunding campaign through the Path of Exile site. The $10 tier allowed players to access the beta -- and the campaign ended up netting the company over $2.5 million. That campaign has metamorphosed into a permanent rewards-based structure for monetization: "it's more our business model than crowdfunding" at this point, says Wilson.

Players can buy time-limited supporter packs that contain credit for microtransaction purchases as well special perks. For example, the Warrior Pack (on sale now for $120 on the game's site) includes exclusive cosmetic in-game items as well as a digital soundtrack and a special title on the game's forums. It also comes with 1100 points -- the equivalent of $110 in in-game currency -- which can be used for microtransaction purchases. Currently, the cheapest supporter pack the developer offers is $50, and the most expensive goes for $900. Players can also buy credits in increments as low as $5. This mix of rewards and currency has proven instrumental in monetizing the game with its player base. "People are inclined to buy supporter packs and then buy microtransactions with the credit they get from those packs," says Wilson. While microtransactions already offer "enough money to run the company on," the supporter packs mean that "fans are more inclined to donate larger amounts of money to the project," Wilson says. "There's a sense of urgency... with the supporter packs." He also maintains that players want to "support" the game because its free-to-play model was designed to have no detrimental effects on gameplay. "We've been careful when designing the game so there's no paying for game content or advantage in the game," he says. "We've purposefully divorced any game mechanics from the monetization." His conclusion? "They give us money because they like what we're doing." Wilson says he agrees with a lot of other game developers who are free-to-play skeptics, and that his studio's "philosophy was that if you were going to the shop and buying a retail game using the old model, you'd expect a lot of value form that box," and that's how it approached Path of Exile's development.

Where Things Get Weird

The expense of the high-tier packs is notable, however. Still, says Wilson, the company has been careful to monitor the spending of its whales. He speaks of a time-limited kiwi pet that cost $1,000 and "became such a status symbol" that it sold out quickly. But he also says that his players estimate their likely microtransaction spend over a long period of time and go for the supporter pack that will enable them to play over that period after making that careful consideration. Players have even approached Grinding Gear about putting more expensive supporter packs on payment plans, an idea that the studio does entertain. When that happens, "we look at the situation behind it," says Wilson. The studio has turned away players who have attempted to live beyond their means, he says. Path of Exile's second set of supporter packs included one that sold for $12,500 but also generated a lot of interest from players who couldn't afford it. "We had to make a few judgment calls. If you can't spend $12,500 at one time... several of those offers, we had to turn down," says Wilson. Grinding Gear ended up "encouraging people to buy cheaper packs they can afford now." The company has not since sold such an expensive pack, he says. When it comes to his player base, says Wilson, "I don't think they're generally spending more than they can afford. We just make sure we're not accepting any offers that make it seem like that's the case."