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I went into the launcher and press play but it crashed, even though it was working fine yesterday

Forge Version: 1.7.10-Forge 10.13.4.1481-1.7.10

I Tried it with different mods but they all didn't work but I hope this can help anyway:

Original mods before crash: AntMan mod, Bibliocraft, codechickencore, customnpcs, Legends core, renderPlayerAPI, SuperHeroes Unlimited.

[19:48:19] [main/INFO]: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[19:48:19] [main/ERROR]: Unable to launch
java.lang.ClassNotFoundException: cpw.mods.fml.common.launcher.FMLTweaker
at java.net.URLClassLoader.findClass(Unknown Source) ~[?:1.8.0_91]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:106) ~[launchwrapper-1.12.jar:?]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at java.lang.Class.forName0(Native Method) ~[?:1.8.0_91]
at java.lang.Class.forName(Unknown Source) ~[?:1.8.0_91]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:98) [launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release

full log please?

that was the full log

crash report then?

There's nothing there to diagnose other than it wouldn't launch.

maybe upgrade to 10.13.4.1558 version of forge, but thats about all I got.