When you start minecraft with the forbidden magic mod, minecraft crashes, everything works fine without it
log:
[00:17:52] [main/INFO]: Setting user: NaKaTa_
[00:17:54] [Client thread/INFO]: LWJGL Version: 2.9.1
[00:18:03] [Client thread/INFO]: Reloading ResourceManager: Default
[00:18:04] [Sound Library Loader/INFO]: Sound engine started
[00:18:05] [Client thread/INFO]: Created: 16x16 textures/blocks-atlas
[00:18:05] [Client thread/INFO]: Created: 16x16 textures/items-atlas
[00:18:09] [Client thread/INFO]: Stopping!

I start Minecraft with the mod just fine without any problems. This log doesn't even tell me anything.