Mystery of the Targeted Merchants

Naruto, Chouji, and Yurinojou take on Ruiga, who uses water as a weapon. Ruiga has the power to draw out water from the Earth, giving him an unlimited supply of ninja weapons. How can they defeat an opponent who has a limitless supply of water? Even if they can win, can they defeat the second ninja, Jiga? Also, what is the Princess' true motive for running away?