For those who have not completed games in the Xenoblade Chronicles series, this page contains spoilers regarding the plot. Discretion is advised.
The Dragon Summon is a switch in Xenoblade Chronicles. It is located at the top of Basverg Belfry in Prison Island. Activating it rings a large bell, causing the Dragon King Alcar to appear in front of the altar in the Corridor of Silence. The boss must be defeated to obtain an item which is needed for Path to the Top.