Explanation: Flaming pigs were an occasional device used in antiquity to counter enemy war elephants. The pigs would be slathered in pitch and set on fire all at once, then loosed towards the elephants. The squealing, burning pigs sprinting towards them would terrify the elephants and disorder them (ideally into each other, or even into the enemy lines). G'wan, git'em!
One of the big problems with war elephants is that you do not want six tons of weaponized meat getting, in any way, out of control. Training elephants to not panic at groups of armed men is (relatively) easy enough, since armed men are easy to come by when training a military force - but who thinks to train their war elephants to not fear burning pigs sprinting under their feet? SCREAMING BACON FLAWLESS VICTORY