The door is no ordinary door; it is made from a special kind of ironwood found in the Secret Realm.
Its hardness far surpasses that of ordinary wood.
One could say its hardness doesn't fall much short of that of iron.
Moreover, this door is a full five to six centimeters thick, even the two from the Zhu family might not be able to achieve this feat.
Thus, everyone present knows that the person who arrived is very strong.
But who exactly could it be?
At this moment, the people inside the room are all perplexed.
"Cough, cough, cough!" A series of coughing sounds came from outside, the voice was quite elderly.
The two from the Zhu family heard the sound, and confusion appeared on their faces, "Old man?"
But Xiong Hu and Xiong Hai, who were struck dumb by the wooden plank, turned pale instantly.
"Grandfather?"
The two exchanged a glance and saw disbelief in each other's eyes.
