No revenue estimate for GOG — its rating/review counts don't calibrate to sales the way Steam's do. The Steam version is estimated at $295.5K — a different platform, not this one.

Moon Mystery

The Moon. Our closest celestial neighbor. A place full of mystery and strange things. That's right, there's more than just rocks and impossible challenges out there. A lone astronaut is about to learn that first hand, when he loses contact with Earth and begins an interstellar odyssey across the universe Moon Mystery is a first-person shooter adventure full of puzzles, action, set on strange new worlds. The gray rocks of the Moon are just the first step on a great journey. Fill up your oxygen tanks, top up your magazines, and get ready for a long trip. You won't be seeing Earth for a while. Humanity's return to the Moon was no easy feat, requiring state-of-the-art technologies and Artificial Intelligence. Piece together what happened to the previous mission on the Silver Globe alongside the sole survivor, the AI computer. Our first permanent lunar base being the origin point for where everything went wrong. What happened? What do you need to prepare yourself against? Just why did we go to the Moon in the first place? The Moon is one of the most hostile environments known to man. Put wits and platforming skills to the test while traversing treacherous landscapes and vast abandoned bases. Pilot multiple vehicles such as spaceships, radio-controlled cars, lunar rovers, and even a submarine to get through alien worlds and solve the many puzzles that await. While outsmarting puzzles and platforming through the environment is one thing… Dealing with malfunctioning robots stalking the corridors alongside other, more terrifying and mysterious foes, is another. Keep that gun loaded alongside oxygen bottles, you'll need it.