A downloadable game for Windows

Buy Now$4.99 USD or more

Isostasy. Equilibrium. The balance between opposing forces. Hot and cold. Solid and liquid. Light and dark. Peth-Luk and Gol-Luk, the gods that emerged from the Isostasy at the initiation of the current Fathom...but those are only myths...

You play as Beihnn. Explore eight different zones with different terrain. Find items to help you progress, talk to other characters for hints, solve puzzles, and figure out how to defeat 9 different bosses.

The .NES ROM file is playable on any NES emulator or flash cartridge that supports the UNROM mapper (almost all do). I recommend Mesen.

The standalone Windows PC version has the ability to save games, including all explored map data, to a save file in your Documents folder automatically upon viewing your password. If you have a valid save file, it will auto-populate on the Enter Password screen. Extract the contents of the zip file to your preferred directory and run Isostasy.exe to play. You can then right-click Isostasy.exe and select "Pin to Start" to create a shortcut on the Windows Start Menu. To reach the settings screen (including controller configuration) press Select or the D key while the game is paused.

(Version 2.2 is the current official version of the game. I have left version 1.0 available for players who may prefer it for some reason. It contains glitches and sequence breaks that may be useful in speedrunning.)

The Isostasy website, including game instructions.

Isostasy is designed to be played with a monitor refresh rate of at least 60 Hz. Playing with a refresh rate below 60 Hz may result in a sub-optimal experience. If audio or video issues are encountered, please check your monitor's refresh rate and increase it if necessary. Also note that in a multiple monitor setup, the refresh rate of all monitors may be limited by that of the slowest monitor, depending on your hardware. Try turning off or disconnecting the slower monitor and see if that resolves any issues.


Buy Now$4.99 USD or more

In order to download this game you must purchase it at or above the minimum price of $4.99 USD. You will get access to the following files:

IsostasyV1.0.nes 64 kB
IsostasyV1.0.zip 27 MB
IsostasyVer2.2.zip 27 MB
IsostasyVer2.2.nes 64 kB

Download demo

IsostasyV2.1Demo.nes 64 kB
IsostasyV2.1Demo.zip 27 MB

Development log


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How big is the demo? I've just reached the Marine area, and wondering how close to the end I am.

You're close. The demo omits the last 2 zones, Space and Fortress. once you exit the Marine zone you'll get a message thanking you for playing the demo and asking you to buy the full version. 

I have been told that the demo is too long, but I wanted to give people a fair chance to decide whether they really wanted to finish the game before paying for it. if a player gets to the end of the demo and says "meh, that's good enough, I'm done now", then that's OK with me.

Yah, if your goal is to sell copies, I would agree with them about it being too long. 

I'm currently working on a new version to fix bugs, clean up some graphical issues, etc. I may release a new demo that only includes half the game instead of 75%. But to be honest, I'm less concerned about money than that people enjoy playing it.