Beyond All Reason is an incredibly impressive free and open source RTS, with The Lightbringer update out now that's a huge advancement for the visuals. If you love massive battles you need to play this one.
The update was getting so big, they've had to split it into multiple parts, mainly because they kept on adding more.
A full day / night cycle system should come in Part 2. For Part 1 that's out now you can look forward to seeing dynamic animated detail lights on units and buildings, with the developers noting they've added in "over 3,000 individual lights across nearly 400 units" and it looks seriously cool. On top of that there's screen-space raytraced shadows (SSRTX), shockwaves and heat distortions, major performance improvements for the UI along with it being clearer to read and lots more smaller details.
The amount of players continues to grow too. They said they've seen the daily active player count double since the start of 2025, "now surpassing 15,000 every single day".
Check out the brand new trailer

Direct Link
While the game is technically considered in Alpha, it's fully playable and has Native Linux support.
It will release on Steam eventually but they still have a lot of work ahead. For now, download direct.
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