Ending the war was not enough. The Tree had been reduced to the Great Seed and its mana was too depleted to carry the burden of the entire world. Using the Eternal Sword, I split the world into two halves, arranged as in an hour-glass - mana flowed from one half-world to the other, and before the declining world could reach too dire a state the process would be reversed.

[Perhaps the precise details are unnecessary, but honestly his handiwork deserves some recognition.] In short, yes, I saved the world.