The mind of a wizard is more open to the more esoteric elements of his surroundings - this is why he is able to perceive the weave of the Great Tapestry that is the multiverse, and pull at the strings. This increased sensitivity can manifest in several ways.
All magic is suddenly gone. No mage can sling sorcery anymore. This upsets all empires and civilizations. It is soon discovered though, trough the combined work of mystics, scholars and dreams, that all the magic has been drawn into a single orb in a vast tower located at one of the poles. Whoever gets there first wins the greatest price in history, access to all the magic in the world. But who owns the tower?