If you like puzzles, Half-Life 2, and physics, then you’ll probably like this little free tech demo-esque game called Transmissions: Element 120. Where you’ll venture through tunnels and various rooms, solving puzzles and discovering some pretty neat and unique mechanics that I’ve only seen here in this game. It also has 11 achievements (That are pretty easy IMO), so you can go hunting for those if that’s your style.
Here’s the Steam store page for it. And a reminder that it’s 100% FREE!