Want to preface this by apologizing in advance if what I'm on to here is something already widely adopted. But it feels new to me and it's absolutely changing how successful I am on higher difficulty. I tried searching a little but did not turn up anything here. I'm naming it "Micro Trading" and it's the way I am able to both accumulate more GPT in the early game while diminishing the GPT of the AI civs. Before I get in to the trading, I have to say it is highly dependent on some other, often random, successes that can be had early game. Ideally you want to quickly suzerain one or two CSes to get more Diplomatic Points rolling in. And you want to have quickly improved one or more Horse and/or Iron resources. Better still if you are not able to build Horsemen or Swordsmen yet and have no use for them. OK, so here's how it works. You're still in the early stages, have met the basic requirements in the previous paragraph, have met a few AI civs, and are working out your next moves. Who to try and befriend, who is going to sneak attack you, who is vulnerable to your taking them over. You start offering horses, iron and diplomatic favor for GPT. But wait, there's more! And this is the critical part. There seems to be a sweet spot, changes a bit with what era you're in, for the amount of your resources to trade. For example, you might outright offer 20 horses (assume to an AI who has room for 20) and they will give, say, 4 GPT. However, if you offer only 7 horse they will give 2 GPT. Offer 7 again, they respond with 2 GPT. Do it a third time; you've now parted with 21 horse but gained 6 GPT. Whereas if you'd sold 20 wholesale you'd only have gotten 4 GPT. If/when I have enough improved resource tiles and/or plenty of favor I find that I can bleed an AI civ dry in relatively few turns. I try to pick out the AI who has the biggest GPT to whittle down. In my current game, normal speed, I'm at turn 77 and have been trading with 3 AI civs for 10 or 15 turns. When I began, one, Spain, was generating over 30 GPT when I was at 3 GPT. After repeatedly offering them horses, iron, and dip they currently are earning 5 GPT and two other lesser earning civs are below that. I now have 43 GPT of which 33 GPT are from active deals. I sometimes have reservations about trading the Diplomatic Favor in particular, but there really isn't a great use for it early game most of the time, and lots of time still to make up for it. I will stop trading as many resources after I can build/upgrade my own units with them. But in the past I would simply let horse and iron fill up, top off, and you're prevented from accumulating more. So why not offer them up?