This one has a couple of pretty significant balance tweaks that folks should really appreciate. Firstly, the Fallen Spire exogalactic strike forces are a bit better tuned. Secondly, the youngling nanoswarms now really are better at their job of hitting a lot of targets. And thirdly, the AI fortress health has been halved, making them not remotely such a grind as they were.
This is a standard update that you can download through the
in-game updater itself, if you already have 4.000 or later. When you
launch the game, you'll see the notice of the update having been found
if you're connected to the Internet at the time. If you don't have 4.000 or later, you can download that here.