In the silent room, the black crystal box before Lu Xuan began to tremble slightly without warning.
Though there was not a trace of wind in the surrounding space, the lid seemed to be gently pushed by an invisible hand, slowly lifting open.
Inside the box lay a miniature black tree, barely the size of a palm. It looked ordinary, yet it emitted an indescribable aura of gloomy radiance.
The instant Lu Xuan opened the box, a vast, boundless black current of air burst forth, as though it had finally been released after being imprisoned for ages.
The black current surged outward with the speed of thunder, too swift to cover one's ears.
This black current, brimming with vigorous vitality, came in with overwhelming force, as if it intended to break free of the room and sweep into the outside world.
Yet at that moment, outside the room, a purple barrier of air radiating mysterious light appeared in the sky.
Like an enormous purple dome, it tightly enveloped the entire room.
This purple barrier was incomparably tough and emanated an extremely terrifying aura.
It firmly blocked the wildly surging black current, preventing it from crossing the line by even a single step.
Having learned from his previous encounter with a Top Grade Heaven and Earth Spiritual Object, Lu Xuan immediately used Divine Sense Power to seal this patch of heaven and earth.
This prevented the terrifying Heaven and Earth Spiritual Qi within the Grotto Heaven Spiritual Object from leaking out and causing a shocking storm of Heaven and Earth Spiritual Qi.
A faint trace of shock showed in Lu Xuan's eyes. The sight before him left his heart deeply shaken.
The Heaven and Earth Spiritual Qi in the room was so dense it had nearly condensed into a visible mist,