Nino Island is composed of 4 levels with level B4 being the ruins itself. Level B1: The hangar; reached by taking the elevator with the "up" sign from the Defense Platfom. You'll first come to a room which contains the broken-down Parabola Gun and a ladder leading to the roof. After the encounter with Glyde using the Parabola Gun, this area is sealed off. Level B4: The Nino Ruins and also the Guild Ruins. The entrance to the Nino Ruins will only open up after Glyde and his base have been taken cared off.