If you like physical sandbox games you might want to check out the free version demo for Liquid Crystal, which was recently announced by Kotsoft. However, the particle physics simulator is pre-alpha, so changes will likely be made before its official release, but you can still download it and have fun.
In the world of liquid crystals, you can run (or fly) and explore a world made of particles. You can also shoot particles or apply a force of attraction on other particles, like water spray, to see what happens. Each block is physically simulated and can be interacted with, and it has fairly quick and responsive movements, although it is not (yet) a perfect physics simulator.
You can download the Liquid Crystal demo here on itch.io. The minimum system requirements include Windows 10 64-bit, SSE2 support for the processor, a DirectX 11.1 GPU that supports 2 GB and 4 GB of RAM, although the author recommends Windows 10 64-bit, an Intel Core i7 processor. -8700K, an RTX 2080 GPU and 16 GB of RAM.
Since this is a fairly recent download to itch.io, Windows will likely launch the SmartScreen Filter Warning when you try to run it for the first time. Don’t worry, however, it’s easy to get around. When the warning appears, click “More Info” then “Run Anyway”, and you should be good to go.
Source: Grant Kot