Tinybuild has earned $16 million in revenue from books based on its Hello Neighbour game franchise.
That revenue stream is in addition to money earned from the three games that comprise the Hello Neighbour series, which have now been downloaded more than 30 million times.
According to Tinybuild, it decided to publish books with children's author Carly Anne West when it noticed that young players were sticking with the game despite uneven reviews from the critics.
The Hello Neighbour books have sold more than two million copies, generating $16 million in revenue.
"[Indie publishing] stopped being a sustainable business model the minute the number of mid-size publishers exceeded the number of good games being developed," said Tinybuild CEO Alex Nichiporchik in a statement.
"Instead of focusing on one-off publishing deals, it's better to build strong and entertaining brands. That means a large in-house development infrastructure that can support both internal games and external studios."
The Hello Neighbour franchise is available on PC and console, where it is sold as a premium product. It is also available on mobile, where it is free to download.
We talked to Nichiporchik in May last year, as Hello Neighbour was gathering momentum, and its impact on Tinybuild's strategy was already apparent.
"All the games we're signing now, we build a plan for them," he said. "If this initial title takes off in this manner, then what do we do? What is the world behind it? How do we move into merchandising? How do we do movies down the line, or animated shows? All of those things are really key."