(adsbygoogle = window.adsbygoogle || []).push({}); im on rebug 4.21 dex when i put the black ops 2 game cd it give me a error but my other game work why is that

You could tell us what Error code it is.

But I think I know whats the matter, did you installed any updates for BO2?
If not, download a 1.12 pkg for your region and then you can start it.