Once you have a shader loader like Iris or OptiFine running in your game, you need to place and select Ultimate Horror Experience Shaders before its dark lighting and camera filters appear in your world.
Placing the Pack in Your Game Folder
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2. Open the Shader Packs or Shaders menu depending on your loader.
3. Click the button to open your shaderpacks folder.
4. Move the Ultimate Horror Experience Shaders archive directly into that folder without unpacking its contents, unless it is already structured as a single shader directory.
Selecting and Testing the Shader
1. Return to Minecraft and look for Ultimate Horror Experience Shaders in the pack list.
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3. Load into a survival world to confirm the shader is working. Warm colors should immediately look drained into an icy palette, a gritty film grain should cover the view, and the corners of your screen should darken with vignette shading.
4. Place a torch or lantern nearby to verify that block lighting dims and glitches as expected.