While Minecraft Forge is not required if it isn't installed you won't be able to see mobs in mobspawner items. The process for installing NEI has changed. (For the easier AGAIN!). Install FML 3.0.175.332+ OR MinecraftForge 4.0.0.240+ into the jar. Place the CodeChickenCore jar file into the coremods folder. Place the NEI jar file into the coremods folder. Place any modules' zip files in the mods folder. NotEnoughItems. Provides: All NEI functionality.
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