It’s not an everyday occurrence when a game developer double-backs on the game they’re giving out for free. It hasn’t panned out then and it isn’t going to work out well anytime soon, as evident with indie studio Landfall (of Totally Accurate Battle Simulator fame).

The developer surprise-released its new co-op horror game Content Warning on 1st April, free to claim for its first 24 hours. After that period, the game will be sold for US$8. Within that 24 hours, about six million copies of the game were claimed. When it started becoming a paid game, Content Warning sold over 700,000 copies in a week.

Landfall CEO Wilheim Nylund said to PC Gamer that the team was caught off guard by how many people flocked to the game immediately.

“It felt likely that [Content Warning] would be bigger than any of our similar small projects, but we definitely didn’t expect it to happen so quickly. It was definitely a lot of excitement and a lot of confusion about how it blew up as quickly as it did.

We all had this feeling that there’s so much at stake tonight when the game goes paid.”

According to the developers, it did pay off as it cracked 700,000 copies sold within a week. The team hopes it sells a million copies in the first two weeks since its 1st April debut.