Here's the crash report:
java.lang.UnsupportedClassVersionError: mekanism/common/asm/LoadingHook : Unsupported major.minor version 51.0
at java.lang.ClassLoader.defineClass1(Native Method) ~[?:1.6.0_65]
at java.lang.ClassLoader.defineClassCond(ClassLoader.java:637) ~[?:1.6.0_65]
at java.lang.ClassLoader.defineClass(ClassLoader.java:621) ~[?:1.6.0_65]
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) ~[?:1.6.0_65]
at java.net.URLClassLoader.defineClass(URLClassLoader.java:283) ~[?:1.6.0_65]
at java.net.URLClassLoader.access$000(URLClassLoader.java:58) ~[?:1.6.0_65]
at java.net.URLClassLoader$1.run(URLClassLoader.java:197) ~[?:1.6.0_65]
at java.security.AccessController.doPrivileged(Native Method) ~[?:1.6.0_65]
at java.net.URLClassLoader.findClass(URLClassLoader.java:190) ~[?:1.6.0_65]
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:117) ~[launchwrapper-1.11.jar:?]
at java.lang.ClassLoader.loadClass(ClassLoader.java:306) ~[?:1.6.0_65]
at java.lang.ClassLoader.loadClass(ClassLoader.java:247) ~[?:1.6.0_65]
at java.lang.Class.forName0(Native Method) ~[?:1.6.0_65]
at java.lang.Class.forName(Class.java:249) ~[?:1.6.0_65]

Updata Java.

Okay I just did and it still crashed

What do you mean?

New log?

Grmialiq means the crash that happens after you updated Java.

Grmialiq isn't in the crash report

Think i'm also experiencing this, Client crashen on join whenever there are energfy cubes i think.

@liamnotneeson Sorry, it was a typo. Grimallq means the crash that happens after you updated Java.