My Brain is too small so i need help

Hello Forge!! I created a superpower based smp for me and my friends but one of my friends keeps crashing before he can even finish loading minecraft

Idk what to do so i thought maybe coming here could help since i cant really read this because of my small brain

java.lang.NoClassDefFoundError: slimeknights/tconstruct/library/client/MaterialRenderInfo
    at lucraft.mods.lucraftcore.LCConfig$Materials.<init>(LCConfig.java:108)
    at lucraft.mods.lucraftcore.LCConfig.<clinit>(LCConfig.java:36)
    at lucraft.mods.lucraftcore.addonpacks.AddonPackHandler.getAddonPacksDir(AddonPackHandler.java:61)
    at lucraft.mods.lucraftcore.core.LCClientHooks.insertAddonPackResourcePacks(LCClientHooks.java:37)
    at net.minecraft.client.Minecraft.func_110436_a(Minecraft.java:789)
    at net.minecraftforge.fml.client.FMLClientHandler.beginMinecraftLoading(FMLClientHandler.java:247)
    at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:467)
    at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:378)
    at net.minecraft.client.main.Main.main(SourceFile:123)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
    at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
Caused by: java.lang.ClassNotFoundException: slimeknights.tconstruct.library.client.MaterialRenderInfo
    at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 15 more
Caused by: java.lang.NullPointerException