An angry AI core created by the Brotherhood of NOD. At first, CABAL was merely a puppet of NOD, obeying all their wishes and helping the fight the Global Defense Initiative (GDI).
However, in the firestorm age, CABAL got overloaded on tiberium vines and took on a life of his own.
The AI core now imagined that he was his own being and owed loyalty to no one. He then went medieval on both GDI and NOD, destroying evrything in his path.
Oh, shit. CABAL no longer serves NOD. If he is not stopped, he will kill us all. AAA!!!