Highest tech extorted on Emperor?

[Delphi456]

I'm playing Mongols on Emperor with 31 civs in Monarchy and haven't done any research except Philosophy, which I wasn't the first to discover. I extorted Gunpowder after killing 20 units; raized 3 towns; pillaged capital; MA'd with one other civ. I've set a lone scientist to Chemistry and am warring with another civ to get it in a peace deal. How high up can I go with extortion?

 

[Suisami]

Theoretically all the way. Its just how hard you hit the AI without getting hit hard yourself. It becomes more difficult the more expensive that tech. But really it depends on how much the AI thinks it lost.