It's Astral Sorcery. And I can't live without my Halcyon Days skybox...Is anyone successfully using a texture pack with a custom sky in this pack?
I have tweaked mine a little bit, but I don't think I've ever gotten one to work. Trying to see if it's just me.
Add the overworld (0) to this section:
# IF a dimensionId is listed in 'skySupportedDimensions' you can addAmount it here to keep its sky render, but AS will try to render only constellations on top of its existing sky render. [default: ] S:weakSkyRenders < 0 >