The tactic Alexander employed was copied from the Black Army of the Hungarian king Matthias, who used it against other enemy cavalries.
And the results were usually very good, as it took a very, very, very well-trained horse to not just jump and buck, throwing off its rider before breaking rank and running when faced with a terrifying whirling circle of blazing fire and the swishing sound.
And usually, 50% of the enemy cavalry would break rank and collide with one another in this tactic, proving just how lethal the technique could be.
Alexander copied this specific technique instead of the more usual and popular techniques such as using pikes or the Greek sarissa, which was a really, really long spear for one very important reason.
Because the opposing side had mounted archers.
What did he mean by that?
Well, pikes and sarissas were really good at stopping light and heavy melee cavalry.