The Priestess in the Forest

Yuri and co. have gone through many boxes in order to find the last box but coming up empty. They learn of a box in a lake and go to investigate. There they meet a girl, who turns out to be Urike's predecessor. They find out that this lake and land were barren before the arrival of the box. If they remove the box the lake and the land will die. Yuri wants to leave it and just guard it but when Big Shimaron shows up to take it not knowing or caring if it's the real thing or not.