Join The Community
Co-op horror game Emissary Zero has over 1,700 82% positive user reviews on Steam, where it's sold more than 150,000 copies and surpassed the expectations of its solo creator, who makes the game's development process sound like a string of helter-skelter production miracles.
In a hefty post to the game dev Reddit, indie soloist Rone Vine explains "How I made a horror game that accidentally sold 150k copies." Conceived as a linear horror game with optional multiplayer, Emissary Zero began as a distant Five Nights at Freddy's relative borrowing "things like surveillance cameras, dynamic obstacles, and roaming monsters."
What we ended up with is "a walking simulator with environmental interactions and puzzles" where you pick up and manipulate objects as you explore a mysterious, monster-filled building alone or with up to three friends.
Vine's previous game, the Soulslike Estencel, "took way too long," they say, so after leaving a freelance job in 2024 to focus on Emissary Zero full-time, they wanted to get this done relatively quickly. "Even if this one failed, at least it wouldn't take forever," they wrote.
In a Reddit reply, they said, "Of course I used a lot of assets" as a solo dev with limited resources, but they actually prefer it that way, with no interest in expanding the team or forming a studio. They were in a technical program at college for a year, but say their game dev skills are self-taught.
Emissary Zero was released on March 28, 2025. "I was running out of money," Vine said in another Reddit reply, and launching in March would mean a May payday. "I had no other money left at all" when that first payment eventually came in, Vine says. Its release date was locked in as of January, meaning "delays were no longer possible."
"The last three months were intense crunch," they say. "Three weeks before release, Steam rejected the build due to copyright concerns with one of the characters." This was apparently due to overlap with one enemy and the iconic Slenderman design; once that was fixed, the game was accepted.
"Communication with support and approving the build took a while, but thankfully, it was resolved – two days before release, Steam approved the build," Vine says.
The nail biters and buzzer beaters don't end there, either. The story events were finalized "just two weeks before launch," and the actual story texts were finished "three days before release," with machine translation handling most other languages. "It worked surprisingly well – I haven’t seen any Steam reviews complaining about translation quality," Vine says.
There was literally no marketing, Vine says, apart from a few Twitter attempts that "didn't go well." Launch was "pretty calm," with "Mixed" Steam reviews complaining of optimization and difficulty issues that were addressed in rapid hotfixes.
Vine says reviews picked up, sales "started off well and stayed stable," and then in April those sales "jumped several times" on the back of a viral TikTok video that introduced millions of people to the game.
As of October 5, Emissary Zero has passed 150,000 copies sold and keeps on ticking with Vine "working on a sequel with new ideas I want to build on top of the system from this game. I'd also love to bring it to consoles this time."
"This game was a unique experience," Vine concludes. "It started as a small project, but ended up exceeding all expectations. For me, that’s a success."
