When Steam best seller Vampire Survivors made the surprise jump to mobile last month, it wasn’t just as compulsively playable as its PC and console counterparts, it was also free. And unobtrusively so. In a sea of aggressively monetized and sometimes downright exploitative smartphone games, it stood out all the more. Developer Poncle now explains that the crappy app marketplace is the reason Vampire Survivors’ free port exists in the first place.

Vampire Survivors was itself inspired by a 2021 Android game called Magical Survival, but its explosion in popularity on Steam early last year led to its own clones on the App and Google Play stores as players searched for a game that didn’t yet exist on the platforms. “Months passed by and a large number of actual clones—not ‘games like Vampire Survivors,’ but actual 1:1 copies with stolen code, assets, data, progression—started to appear everywhere,” Poncle recently wrote in an end of 2022 update on the game’s Steam page (via PC Gamer). “This forced our hand to release the mobile game ASAP, and put a lot of stress on the dev team that wasn’t even supposed to worry about mobile in the first place.”

The developer said they tried to look for a business partner to work with them on a mobile version of the game, but nobody they spoke to was on board with “non-predatory” monetization. The biggest App and Google Play store games are all free, but most still collect their pound of flesh one way or another. Many gate progression unless you wait a certain period of time or pay, while others monetize gameplay benefits aimed at milking repeat customers lovingly referred to as “whales.” A few operate like thinly veiled slot machines. Vampire Survivors doesn’t use any of that. Instead it relies on completely optional ads.

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The hit bullet hell roguelike has you fighting ever growing hordes of monsters while you collect upgrades. Every game ends at 30 minutes no matter what, but the better the playthrough, the more gold players earn to unlock permanent upgrades and features you get. The free mobile version of Vampire Survivors capitalizes on this in two ways. On a particularly long run, you can “cheat” and get a second life if you watch an ad. And once you die, you can watch a second ad if you want to retain more of your gold. The completely optional tradeoff makes the excellent mobile version even better.

“If you’re like me [and] wanted VS on mobile, you’d have been happy to just pay a couple of bucks for it and call it a day; but the mobile market doesn’t work like that and by making VS a paid app I’d have cut out completely a lot of new players from even trying the game,” Poncle wrote. “This is why we ended up with a free-for-real approach, where monetization is minimal and is designed to never interrupt your game, always be optional and in your control trough a couple of ‘watch ads’ buttons, and doesn’t have any of that real money sinks that mobile cashgrabs are usually designed around.”

The developer says the experiment so far has been a success, with high user reviews and lots of new players coming in through word of mouth. The only thing now is to figure out how to introduce the Legacy of Moonspell DLC which costs $2 on PC.

“The problems we’re facing are the same mentioned above: how do we make it fair, but also accessible to players who are only into free games,” Poncle wrote. “We’ll figure something out and publish the DLC asap!”