The current Crimson Sky, although now at the level of an Immortal Artifact due to Ning Tian's strength, is a rather formidable immortal sword. If it were in the hands of another, it would surely be cherished as a treasure.

However...

In Ning Tian's hands, its recent appearances have been for slicing sea beast meat, turtle meat, and now dragon heart. It seems to have become a kitchen tool.

But you can't blame Ning Tian for that.