Drift Here is how Hank Johnson articulates the theory behind this map:

"My theory, known as the Nomad Hypothesis, is that Exotic Matter drifts outwards from portals over thousands of years. That ancient XM leaves a shadow that I know how to detect. In the path of these XM shadows, you can often find an ancient civilization, shrine or significant artwork.

These trace patterns helps to explain why an ancient civilization can flourish in one place, but then decay and die. Portals disappear taking their inspiring power with them. Ancient civilizations are built on the portals of yesterday."

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