"Imagine the Earth as a sheet of paper. Touch one spot on that paper with a burning incense stick. As the heat scorches the paper, that spot gradually blackens and then catches fire. That's the predicament the Art Building is facing."
"We try to cool down the Art Building area and set up enough protection to keep the heat from spreading to other areas."
"The source is the thing producing that heat. The constantly spreading heat is what you call those fluctuations. Once a creature's 'ignition point' is lower than that temperature, it catches fire."
"And to avoid catching fire, besides strictly screening out things with low ignition points, you also have to control the distance... if you're not far enough away, even a high ignition point won't keep you from being affected."
"The range over which that heat spreads is called a 'domain.'"
"A domain of contamination."
"It waxes and wanes in strength like the tides governed by the moon. When that 'domain' advances to its strongest point, that's the period known as the 'Gray Fog Invasion.'"
"Entities carrying Supernatural Traits can potentially form domains of their own, while the 'source's' domain is an extremely complex composite domain. It has a bit of practically every trait."
"And when the source's 'domain' develops a pattern like an ebbing tide, those creatures that died on Campus and were transformed into sculptures follow their instincts and the pull of the ebbing fluctuations toward the Ocean near the Art Building..."
"That road doesn't coincide with any road in the real world. In fact, no such road originally existed in the world. But as more and more of the dead set foot on it, it came to be recorded in an 'observable' form."
"The Authorities named this process the 'Returning Tide.'"
"Only those who