bang the purple girl at the beginning, then the quest tells you to go to the emissary .... ask her about the statues and she gives you the quest for the underground slime in the city. to unlock the gates you need to pull a lever outside the city near the wall, its elevated. finally get in to the city dungeon and bang the slime twice, it will uncover the stone you need to get. afterwards place the stone near the tree of the starting area. now all statues are active. good luck.