I had been the Grand Master of Earth (as in the elemental substance) but now I was retired. Six weeks earlier, I had passed the baton to my student, my star pupil, and begun the long journey home, where I would rest and live out my days growing a garden and enjoying the peace and tranquility of my land. However, as I was almost home, my student suddenly appeared next to me. "I just learned a new power, one that you didn't teach me," he announced, and showed me how he had managed to extend his powers of Elemental Earth over metals, especially ferrous ones-- he could make iron filings dance on his hand like a ballet. I, too, could do such things if I wished, but I had not taught him about it because I had hoped to not encourage the world's movement towards ever-more forged-metal items. But now it seemed inevitable... My pupil had clearly Gone Bad, because he suggested that we return to the "civilized" world (where I had left him) and take control of the armies and kingdoms with our powers. How could I not have seen this coming? I told him it was not our way and that he should abandon such thoughts... "Fine," he said, "You go home, then, and I shall rule alone." With a wave of his hand, stones rose up out of the muddy dirt path, thousands of them, forming a cobblestone road all the way back to my home. Then he disappeared. Of course, I realized that I would have to go back and stop him, so instead of continuing down the path (now road), I turned back.
When I got back to the "civilized" lands, he had already begun his campaign against the Kings, and they had sent an army against him. But, foolishly, it was an army of armored knights clad in metal. My student stripped all the metal off them in a flash, merging it together into a giant golem-like form, an animate monster fifteen feet tall made of shreds of forged plate and chain link, and it began to tear the now-unarmored men up.
The fight was taking place in a giant forest, however, and so I pulled up an Earth power my student apparently hadn't figured out yet: We also commanded plant life, as well as metal and stone. One by one, the trees of the forest leapt from the ground, coming together to form a wooden giant many times larger than his metal one. It easily crushed his metal monster and, with a flick of one finger, knocked him over hard enough to drive the wind from his body.
I stepped over to his prone form. "Just be glad none of the other three are here to see this," I said, referring to the other Elemental Grand Masters. "And be glad you were not any of their students, making this betrayal. My sister, Water, would punish you by commanding the very blood in your body to leap out of you."
And then I turned him into stone.