*Please note* This was designed for scientific accuracy, not gameplay. It will very likely kill your character, crash your computer, and say bad things about your mother.
1) Using MC's default launcher, download Minecraft 1.8.0 and make a copy of it (it is in .minecraft/versions). Rename the copy to 1.8.0NeutronStar.
2) Download the Neutron Star mod.
(THIS IS NOT THE LAST STEP. YOU STILL NEED TO DOWNLOAD THE WORLD AND THE RESOURCE PACK)
3) Navigate to your newly created 1.8.0NeutronStar folder and open 1.8.jar with winrar or a similar program. Delete META-INF, and drop the contents of mod.zip into the .jar file
4) Download Magic Launcher. This isn't totally necessary, but I prefer it over MC's default launcher for using mods.
5) Download optifine OptiFine 1.8.0 HD U A3 and drop it into your Mods folder (This is necessary to see the sky)
6) Run Magic Launcher. Press Setup and click "new" under configuration. Enter a name and leave "copy from" blank. Under Environment, select 1.8. Beside "minecraft.jar", click Select and navigate to 1.8.jar within your 1.8.0NeutronStar folder. Under the Mods tab, click Add and select OptiFine 1.8.0 HD U A3. If you have any other mods checked at the bottom, uncheck them. Click the Advanced tab and change the Memory to the highest your computer can handle. 4096 seems to be the minimum for never crashing. Press OK and ignore the warning.
7) Download the Neutron Star Sky file and drop it into your resourcepacks folder
8) Download the Neutron Star World file and drop it into your saves folder
9) Run Minecraft from the profile you created in Magic Launcher. Apply the resource pack. Go to Video settings and slide Render Distance to 8 (You can go lower, but anything lower than 8 won't display the sky properly).
10) Run the world and give it a long time to load. Pray it doesn't crash. It probably will.
Space Engine: http://en.spaceengine.org/
Music: RedQuadro - Morning Wave (Tunguska Electronic Music Society)
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