From Forgotten to Famous: How a Modded Undertale Blew Up a Random Indie Game on Steam!

Imagine this: You’re an indie game developer, you released your first game years ago, and it didn’t quite set the world on fire. It’s sitting there on Steam, quietly gathering digital dust. Then, one day, you check in, and BOOM! Your neglected game has hundreds of new reviews and a player count that’s gone through the roof. Sounds like a dream, right?

Well, that’s exactly what happened to RetroSpecter, the developer behind Crashphalt. This platformer, launched back in 2018, had a pretty quiet life on Steam. For four years, it barely scraped together a dozen reviews. But then, a few months ago, RetroSpecter noticed something incredible: Crashphalt suddenly had over 500 new reviews, and its daily player count had skyrocketed by a staggering 1700%!

But here’s the kicker: Almost none of these new reviews were actually about Crashphalt. Instead, they were all talking about another beloved game: Toby Fox’s iconic RPG, Undertale. Reviewers were asking, “Does ANYONE want to play Undertale with me???” or simply declaring, “Undertale is a pretty cool game.” Naturally, RetroSpecter was left wondering, “Okay yeah I like Undertale too, but wtf is going on?”

The mystery soon unravelled. It turned out that Crashphalt was powering an ingenious workaround for a fan-made Undertale multiplayer mod called “Undertale Together.” This mod, by default, only supports local co-op. But gamers, being the creative bunch they are, found a clever hack to enable online play using Steam’s Remote Play feature.

Here’s how it works: Players discovered they could copy Crashphalt’s installation files into their modded Undertale directory. Then, by simply renaming the Undertale executable file to “Crashphalt.exe,” they could trick Steam into thinking they were launching RetroSpecter’s game. Since Crashphalt has Remote Play enabled, Steam would then allow them to play the local-only Undertale mod online with friends!

This bizarre surge in activity kicked off around December 2022, perfectly aligning with a YouTube video that explained this very hack. And it wasn’t just for Undertale; the same trick worked for Deltarune too, leading to another spike in Crashphalt’s player numbers when Deltarune’s full paid launch hit Steam in June 2025. Why Crashphalt specifically was chosen for this hack remains a bit of a mystery, as RetroSpecter noted that “the only requirement for the hack is that [it] has Remote Play enabled, and I guess it does help that Crashphalt is free.” There are many free games with Remote Play, so Crashphalt truly was just the lucky pick!

Despite his game being used as a mere vessel, RetroSpecter has taken it all in stride. He expressed genuine excitement, saying it’s “really cool to see that the game has found a second life,” even if it’s an unconventional one. He also shared how Undertale was a huge inspiration to him when he started game development, making this whole situation even more special. It’s heartwarming to see such a positive response to something that could easily be seen as an annoyance.

And in a playful twist, RetroSpecter even had a message for Undertale’s creator: “Toby Fox. If you read this, let me know if you… like… wanna make a game together. Thanks.” Who knows, maybe this unexpected story will lead to an epic collaboration!