Backstory: In this current game, I had a slow start because I was attacked early on in the ancient age by Korea which slowed me down. After building my cities up and staying out of the wars going on, I managed to out research the top civ Sumeria and obtained replaceable parts well before they did. At this point Sumeria already owned half the continent and was starting to take over on the side I was on. Using my infantry which Sumeria had no counter to, I joined in the war with Korea/Arabia/and what was left of India. After a while of fighting I manged to push back Sumeria all the way back to their original core but this was only because England on the other side of the continent who was just slightly closer to Sumeria attacked them and drew most of their forces to that side. Now I have managed to gain peace with all the remaining civs but i fear if I don't do something about Sumeria, they will be unstoppable. Also after I got the peace treaty with Sumeria they were still at war with the 1 lone city of india and had just finished killing England. I soon got to see how scary Sumeria really was when they started sending huge stack after stack after stack of units through my land to reach India. Another thing, just with Sumeria's initial attack towards me, before they got distracted by England, they brought over 50 calvary with them and around 20-30 riflemen. When they went to finish off india after I got a peace treaty them, I counted well over 100 infantry in various stacks getting sent through my land with a lot more on the way. Now my question, I was thinking of producing a lot of artillery and fighting a slow war to whittle down their forces then counter attack slowly into their land; Is this a good strategy for the current situation? what would you suggest? Another important note, I started my war with the top civ ahead of them in technology and now that civ is ahead of me and starting to run away in the tech race. Me and that civ are the only 2 civs so advanced so I can't just trade techs to catch up The game difficulty is Monarch, it is max on ai aggression, accelerated production is on, and domination/conquest are the only victory conditions, and I am also playing as Germany.