How large was the entire spatial bubble region? No one had ever dared give a definite figure. Even the great scholars of the Demon Lord's Army who had once "calculated the entire universe" had only provided a rough theoretical value for the boundary of the spatial bubble region. No one knew exactly how many spatial bubbles lay within that boundary. People only knew that, since the dawn of history, they had explored merely a tiny part of the "entire world" they lived in. Even the oldest elves and spirit races had never set foot on the desolate outer reaches of the bubble region. Moreover, even among the planes people had explored, only a minority had truly been developed into homes—habitable spaces were few and far between. Most spatial bubbles were abandoned immediately after being explored: no resources, no air, deadly radiation, no water, and poisonous soil... Countless slaves sent out to scout had marked countless uninhabitable planes with their lives. Even the greatest archmages of the Human World were unwilling to build their mage towers in such places, because there was nothing to be found there—except for a handful of mad mages. But those lunatics were not worth discussing.
Mortals were creatures that easily made themselves the center of everything. Just as the people of Earth had once firmly believed they stood at the center of the entire world, the scholars of the Human World had also established a crude model after continually exploring spatial bubbles. They placed the habitable planes they had discovered in the middle of the model, then arranged the spatial bubbles according to their desolation—the farther "out" they went, the harder it was to sustain life. This crude model had no boundary. Beyond a series of border planes, it bore only a general note: Beyond this