Super lategame

Hey!

I have trouble finding ways to win super late game. I have played a bit Western Diplomacy lately, and it isn't very uncommon to have 100k of every reasourses and 500 pop. I find civs like persians or other elephant civs win every time. How can you counter 200 ballista elephants and 150 battle elephants with 50 bombard cannons in the backround? Or how do you counter 300 persian elephants with 200 hand cannoners in the background?

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How do you play super late game maps? What are your strategies?