An alternate dimension which is first seen in Spawn Issues #19 and #20. It is a hellish place, and is home to %^2 and %^9. It is sustained by its inhabitants finding out information about creatures from billions of plains of existence and 'feeding' this information to The Prime. After the atomic explosion plan backfires, and erupts within The Overlap, its inhabitants now have a chance to see what creatures will be affected by the fallout.
The Overlap is said to be the birth place of true magic, here the laws of science are easily manipulated.