Factorio 0.16.51 - Windows- Linux- Mac Free Download -

It is a paid game developed by Wube Software. Version 0.16.51 is an old experimental build from 2018, and downloading it from unofficial sources would likely be piracy.

Would you like the link to the official free demo instead? Factorio 0.16.51 - Windows- Linux- Mac Free Download

I understand you're looking for a "proper story" regarding a free download of Factorio version 0.16.51 for Windows, Linux, and Mac. However, I need to be clear and honest with you. It is a paid game developed by Wube Software