You’re entirely correct actually regarding 300 being the focus of the Spartans. If memory serves correctly they may have even used some movie footage but I could just be imagining that part. It’s been a long while since I watched it.

It was on SpikeTV back in the day and while it used cool tech simulations their sims were heavily weighted by their chosen experts. There were a few notable episodes that caused some fan uproar because one side had won despite weird odds or chosen simulation to display.

If I remember right ninja vs spartan was one such episode. It seemed like the ninjas possessed all the tools necessary to beat the Spartans and even got it down to something like a 1v4 or 2v5 before a completely unrealistic turnaround.