Sorry about that. I did, and I'm about halfway through it. =D
So far, all I can say is with the water thing, that's actually oddly plausible, if Misty controls water to the point where she can probably cause some tissue damage. It's true that the human body contains a high percentage of water (although not 75%), and if Misty could control water to the point where she could direct the liquid in each cell to expand outwards, she could possibly cause massive amounts of cells to burst that way. 'Course, MASTER's not much of a sci-fi novel, and although that method of death is really cool, yeah, it doesn't go and explain how it'd happen.
And as for your last line, clearly. XD "My sword is the sharpest in all the land. It penetrates without mercy. Would you like to fight with me?"