Turning mud to stone is harder than it looks, especially since he first has to move it, then harden it, which are separate, and tiring, skills. Fortunately, Sapphire arrives later in the day, after making some diplomatic maneuvers with the army, to assist, lending her own expertise, if not strength, to his. She also offers some suggestions about the best placement to cover the most of the field. "Though, while your last attempt worked, it might be prudent to test at least one of these, to ensure it'll be as properly destructive as you plan. After all, it would be a waste to do all this work, and then they don't explode properly."