Okay, the story I wanted to write LONG AGO. Not very good, but simply there to explain two changes I made - the ruler and the religion.
Story:
The Gujarati armies were routed. They fought bravely at first, but as their second line unraveled they begun to turn to flight. The Queen was dead, or so they heard. Nothing could save them now, nothing could prolong their existance.
Or so it seemed, until a stray arrow of the last archer that ran his Sarisara in his finest hour. Gujarat - the original home of the Gujaratis before they begun building their doomed empire - was saved. For the moment.
For the Magadhan army was without a commander and the empire without a rule. Kamisara, the heir, was in that time commanding the militias near the Ganges. There, he - with Vishnu's aid - succesfully fought off Aryan hordes. But now, he needed to ride west.
To pick up command over the army.
By the time he arrived, though, the momentum was lost. The Gujaratis retreated into their peninsula for one final battle. Kamisara sent forth ambassadors to incite the Gujaratis to mutiny and surrender peacefully, promising them much good under his rule. But just to be safe, he himself marched out with an army to make sure Gujarat is defeated if it doesn't just give up.
The most remarkable thing about Kamisara was that he was a Hindu, and seeked to make the faith an official one. He needed a military victory, though, to persuade the people and the nobles in the correctness of this decision. In the sky, before the battle, he saw a black swastika against the sun - it was a left-handed one, that of Kali - that of Destruction, and that was what Kamisara intended to bring to his enemies.
To the battle, the Magadhan armies marched with swastikas on their shields. With this, they will triumph.