The Seal

The Seal is a defense created by the Council of Superhumans in order to cease the attacks from Hueco Mundo. The Seal required the strength of all the most powerful members of the Superhuman organization to have enough strength to block out entire dimensions. It is unknown exactly what form’s this wall, but it blocks the ability to open doors and pathways to new dimensions in the Living World, thereby preventing the formation of Gargantas, Senkaimons, and any other way of travel the Shinigami and Hollows have.