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What if a game kept going, all the way down, and all the way up?

An infinite, recursive, tactical shooter for one player.

DRM-Free only

This title is only sold as DRM-Free.

With Inside a Star-filled Sky, I was trying to explore the concepts of recursion and infinity.  Recursion involves performing a self-similar sub-task before being able to complete a main task, and that sub-task may require yet another sub-task.  Recursion is an important concept in computing and mathematics, but we also encounter something like it in everyday life:  we must often interrupt a given task to complete a necessary sub-task, and that sub-task may require yet another sub-task.  "Before I can mail this letter, I need to go to the post office and buy a stamp.  But before I go to the post office, I need to buy fuel for my car.  But before I buy fuel, I need to stop by the bank and withdraw some money."

The subjective experience of recursion, in either mathematics or everyday life, can involve forgetting what the main task was as we delve deeper into this nested chain of necessary sub-tasks.  When we rise back out as we complete each sub-task, we often have to remind ourselves of what we were trying to accomplish in the first place.  "Why did I need to buy fuel?  Oh, that's right:  so I could make a trip to the post office.  Buy why did I need to go to the post office?"

This experience is also connected to our subjective experience of infinity, because in both cases, we feel lost.  Furthermore, in mathematics, recursion and infinity are intimately connected, because a broken recursive algorithm can lead to infinite regress.

I wanted to make a game about all of these concepts.  A game that throws you into an infinite system and lets you take on sub-tasks and sub-sub-tasks in that system.  A game that tricks you into getting lost in your own recursive pursuits and later rewards you with a profound "Aha" moment as you rise back out and remember what it was that you were trying to accomplish in the first place.

  • How to Play

Inside a Star-filled Sky is an infinite, recursive, tactical shooter by award-winning designer Jason Rohrer (Passage, Between).  What if you could enter an object in a level and find a level inside of it?  What if you could enter an object in that level and find another level inside of that?

What if you could change an enemy or a power-up from the inside?  What if you could enter and change yourself? 

What if these levels inside levels inside levels went all the way down---and all the way up?

Inside a Star-filled Sky is a hard, procedurally-generated shmup built around this core concept.

If you are having some troubles with this title, please do not hesitate to check out our Help pages or contact us about it! 

  • Windows

    • Operating SystemWindows XP
    • Processor900 MHz
    • Memory40 MB
    • Storage10 MB
    • GraphicsOnboard Graphics
    • SoundStandard Audio
  • Mac OS

    • Operating SystemOS X version Leopard 10.5.8, Snow Leopard 10.6.3, or later.
    • Processor900MHz Intel
    • Memory40 MB
    • Storage10 MB
    • GraphicsOnboard Graphics
    • SoundStandard Audio



Jason Rohrer has developed and released 15 games since 2004, including award-winning games like Gravitation and Between, and critically acclaimed pieces like Passage, Primrose, and Sleep is Death. He does everything---from programming to graphics to music---by himself.