Enable Grayscale Lightmap Shaders in Your World
Activating the Resource Pack
Grayscale Lightmap Shaders works as a resource pack, so you don't need to install separate mod files. Open your world or create a new one, then pause the game and navigate to Settings > Resource Packs.
Loading the Shader Pack
In the Resource Packs menu, you'll see available packs listed on the left side. Find Grayscale Lightmap Shaders in the list and click the arrow icon to move it to the Active section on the right. The pack will load immediately—you don't need to restart your world.
Once activated, your lighting will shift to the grayscale, retro style. If you want to disable it, simply move the pack back to the inactive list. You can have multiple resource packs active at once, so Grayscale Lightmap Shaders can work alongside other packs that modify textures or UI elements.
Verifying It's Working
The lighting should appear muted and nostalgic compared to standard Minecraft, with reduced color saturation in shadows and ambient light.