From what they could tell, Arthur has grown bigger and taller. His eyes and hair are also no longer red. His hair is green and his eyes are blue, so it isn't exactly their fault that they didn't recognize him.
One of them took out the dossier from their space pouch and checked it to confirm Arthur's identity. They found a young man who looked like him and who entered the Blood Skull sect five years ago.
Now that they recognized Arthur, they were further surprised by his identity.
Someone couldn't help but ask the lady in disbelief, "Are you sure that man is Arthur? They look different and have too massive a gap in their power."