Their realm was in constant conflict between the forces of chaos and order. In which neither side entirely and permanently defeats the other. These these beings carved stone and the spilled blood of the lamb, and created the Zodiac Key. In the 4th generation of their "Century of the Leopard," the Brotherhood's Lawholder discovered as their world calmed their world was weakening, and the Brotherhood's life energies began fading, so they sent the Key to Earth, a world rife with conflict, believing that it would perpetuate the struggle between chaos and order, as the battle was more intense on Earth than in their own world. Scorpio further claimed that there have been many Key-holders throughout history, including the Illuminati, but he is one of the so-called "Chosen."
Scorpio made his first pubic appearance by using the Zodiac Key to unlock the balance between chaos and order, splitting the In-Betweener into his two diametrical halves and keeping the chaos-side in the Brotherhood's realm. He then proceeded to teleport nearly every major capitol city on Earth into the Brotherhood's dimension and threaten to drain Earth's oceans. The Avengers investigated, with one contingent of the team confronting Scorpio and the other confronting the In-Betweener's order-side. The Avengers thwarted Scorpio's plans by reuniting the In-Betweener. The In-Betweener cleansed the dimension, destroying what seemed to be the Brotherhood and restoring the Avengers and the Earth's cities to their proper places in their dimension. In the confusion, Scorpio escaped and returned to the Zodiac, claiming that he fed false information about his motives to the Avengers. The entire scheme was a plan to gather data on the Avengers on behalf of the Zodiac.
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