So I launch my Minecraft 1.7.10 Forge with these mods.
[1.7.10][SMP]DivineRPG-1.4.1.1
[2.2.0] More Crafting Recipes Mod
extrautilities-1.2.11
Mantle-1.7.10-0.3.2a
Pixelmon-1.7.10-3.5.1-universal
TConstruct-1.7.10-1.8.8 (3)
XaerosWorldMap_b1.6_Forge_1.7.10
and THIS pops up...
Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release
[22:16:10] [main/INFO]: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[22:16:10] [main/ERROR]: Unable to launch
java.lang.ClassNotFoundException: cpw.mods.fml.common.launcher.FMLTweaker
at java.net.URLClassLoader.findClass(URLClassLoader.java:381) ~[?:1.8.0_74]
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_74]
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) ~[?:1.8.0_74]
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_74]
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:106) ~[launchwrapper-1.12.jar:?]
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_74]
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_74]
at java.lang.Class.forName0(Native Method) ~[?:1.8.0_74]
at java.lang.Class.forName(Class.java:348) ~[?:1.8.0_74]
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:?]