Some forces are still active in Chaos, following their own rules, not treating the Tao Tomb as a matter of concern, or rather, they wish to rely on their own strength to break the Tao Tomb. True Holy Palace is such a force.
Other forces, recognizing the situation, choose a Great World to take refuge in. On one hand, they use the Heavenly Tao of the Great World to help low-level Immortals break through their realms more quickly and bring forth more Tao Realm individuals. On the other hand, the barriers of the Great Worlds are already resisting the Tao Tomb. Thus, within a Great World, safety is elevated.
There are many reasons, such as those mentioned above.
Purgatory Island is one of these forces.
Among these, those forces that have made the same choice as Purgatory Island account for more than eighty percent.
In the Ancient Great World, Free Demon Heaven, Void Demon Palace, Yin Moon Sect, Dark Barbarian Tribe, and Bizarre Sect all are forces that have come from Chaos.