Travel Through Ancient Times to Become the Most Powerful Mage

[Farming literature + system + historical imagination + fictional history] What? Are you still using catapults and ladders to attack cities? I directly blasted the city gate open from the inside with the "Mighty Heavenly Dragon". What? Millions of troops are arrayed in front of us. We can't defeat them with just a few people? Oh! There was an uninhabited mountain in front of me, so I just "flooded the seven armies" and destroyed them all. What? You have too many cattle, sheep, and horses to keep? Is it possible that grass will grow out of the ground tomorrow? "Host, I am the most powerful material system, with endless supplies that can be called at any time." "What? The most powerful spell system? No consumption, no forward movement" "Host, you used it wrong." "Yes, this is a dimensionality reduction attack."