In Gehn's home, return to Temple Island by means of the Linking Book. Go through the tunnel to the elevator and press the button take you up one level. Go through the golden Dome to the Gate Room. Go through Position 1 and turn right going down the stone steps. Return to the place where you first arrived on the island, at the telescope. Use the code from Catherine's journal to open the hatch. Look through the view finder to see stars in the fissure. Pull open the pin that blocks the telescope's descent by clicking on the support strut to the left of the hatch, and then swinging the lever handle up. Step back to the main controls and pull down the lever to the right of the scope. Repeatedly press the button until the glass breaks. Now watch Riven destroy itself. Atrus comes through from the chamber in which you first arrived on the island. Catherine arrives a moment later and they embrace. She tells you that the villagers are safe in the Moiety age. You fall into the fissure.
CONGRATULATIONS! You have successfully completed Riven.
