Turning On the Shader Pack
Once Retro Pixel NES Style Shaders is placed in your shaderpacks folder and you launch Minecraft with a shader loader such as Iris or OptiFine, load into any world or stay on the title screen to activate it.
1. Open the pause menu and select Options.
2. Click Video Settings, then open the Shaders or Shader Packs menu.
3. Click Retro Pixel NES Style Shaders in the list of available packs.
4.
Confirming the 8-Bit Effect Works
Step into an outdoor area with trees, terrain, and mobs to confirm the classic 8-bit art style is active. Normal Minecraft shading and fancy lighting effects should be completely gone. Instead, both blocks and mobs will display a flat, pixelated appearance with bold, flat colors that mimic an old console video game.
If your world still has standard smooth shadows or unaltered vanilla lighting, reopen the Shaders menu and make sure shader rendering itself is toggled on at the top of the screen. Also verify that the pack was placed inside the shaderpacks folder rather than resourcepacks, as Minecraft will not load shader files from the resource pack menu.