The Great Wall is an example of the effect of the Limit of Questions being passed. It is a large, unstable area of whirling trapar winds visible from outer space. It was created more than 3,000 years before the beginning of the series, when a large portion of the Scub Coral was abruptly awakened from its dormant state. The Scub Coral managed to put itself back to sleep before the Limit of Question's consequences engulfed the entire planet. Common physical laws no longer apply in the area encompassed by the Great Wall
In the series, the debate over the origin and nature of the Great wall is a heated debate between scientists. Dr. Bear theorized that a meteorite struck the planet 3, 000 years ago and caused the Scub Coral to awaken, but forcing itself back into its dormant state created the Great Wall. Other scientists, commonly Mischa, disapprove of this theory but offer no other explanation for how the Great Wall came to be. Adroc reached the accurate conclusion that the Great Wall was created after the large number of lifeforms on the planet caused the Scub Coral to wake up and went back into dormant state to prevent the Limit of Questions from being activated. Renton, Eureka, and the rest of the Gekkostate and military later find out the truth near the end of the series.