Factorio is a factory building game, which has been around since some time. Its developer Wube Software released a year-end update where they confirmed that Factorio has sold 3.5 million copies so far. Considering that the game has quite a niche theme, it is really a great number to reach.

Wube shared a blog post and said “This year we have reached another sales milestone, with 3.5 million sales being passed this Christmas. We are still having steady and consistent sales of about 500,000 each year, which in retrospect validates the original no-sale policy we have stuck with since we launched on Steam in 2016.”

The blog post also includes an expansion teaser, some updates related to development and statistics. Teasers included a Christmas postcard, some sneak peek content such as new item icons and more. Players are guessing that the red icon looks like a blast furnace. Other icons are thought to be a sealed vacuum chamber and some sort of electrical device.