C1249 Ambush(part i)
Blood Firmament was indeed a Great Immortal Artifact, and it was a pure defense Great Immortal Artifact. Under full strength activation, it could block the attack of an expert of the fifth level of Immortal Stage with all their might, and even an expert of the Ninth Layer of Immortal Stage would have a certain degree of defense.
Of course, if the Blood Firmament was this simple