Did you mean , is there a need to OC , for WoW , or to run WoW well ?
One doesn't really overclock software , they overclock the platform that its running the software ( IE your hardware , )
For Wow you will be fine with an i5 4690 , if you are running at 1080p like most people . If you want to get higher resolution than that you might want to consider it but if you have no experience of overclocking i'd suggest you stick with a non K edition.