Overall - the demo is very polished. I did not encounter bugs that prevented me from accessing some parts of the game or hindered the enjoyement. What it now needs is more diverse upgrades, I feel, to create the possibility for player to have their unique playthroughs through the atmosphere
Feedback
1. The mining of the crystals felt very good and crunchy
2. Intro, art and the story hook are very solid
3. The process of exploration is enjoyable, but the battery management feel incredibly limiting. Some of the times I died a few paces from the exit, without any opportunity to mitigate this. In such way cool events like falling somewhere deep actually create a feeling of "oh no, my run is over" - which can be cool if the player has some way to actually mitigate the challenge
4. When Solinyako walks in the mines, his sprite shifts phazes from side to side (like vibrating), which washes away the image a bit, creating a weird distraction
5. The shooting is fun, although when I was playing in a browser, I felt like the sensitivity was very slow