The question is, what if Massinissa (Numidian Prince during the 2nd Punic War), decided not to join Rome during the 2nd Punic War. His rival for the open throne, Syphax, was convinced to join Carthage afterwards, and was a neutral party in that war up to the time. Massinissa decides to join Rome because they're winning at the moment, and look to be giving a better shot of him winning the throne. So, if Massinissa decides to stay with Carthage, and Syphax stays neutral, does the Battle of Zama change (Massinissa fought in the battle with Rome, and supplied Rome a lot of superior cavalry to what the Romans had); with no Numidian cavalry for the Romans?