After getting to the point of always whomping on the computer on Regent level, I started my latest game at Monarch level. I was the Chinese and started on a continent with 5 other opponents. After some ancient wars, it was just me and the Persians controlling most of everything. So around 1400 AD everything settles into a peaceful phase and I begin doing a massive program of infrastructure building along with building more military and cannon, because eventually I'm going to want to knock Xerxes off the map. By 1700, the buildup has been going well. I've snagged all the Industrial Age wonders and have the factories and railroads almost all in place. I'm beelining for Motorized Transportation and get to it before anybody else. Just as my first batches of tanks are popping out of the core cities and just after I built the Intelligence Agency, I see what looks like almost every one of Xerxes' units crossing into one tile on the border. I right-click on the stack and see about 150 Persian units--Infantry, Riflemen, Immortals, and 1 musketman. All in one tile, all in one stack. And this was just too juicy. I had figured on going in to his territory to slug it out, but now Xerxes had just sent almost all of his forces right to where I could bring every piece of artillery, every early tank, every cavalry unit, every extra infantry to eat it alive. In the ensuing carnage, I had a turn where I generated a GL, built an army and had it win a battle, got another GL, built the Heroic Epic, got another GL and built the Millitary Academy, got another GL and rush-built a factory. That was all in one turn mind you. After about 4 turns, the military advisor told me we had a strong army compared to Xerxes. So that's the biggest Stack of Doom I've ever seen.