Sincere Promise.

The people in that house care about their house very much. They don't want it to be destroyed and also want to sleep. But they can't sleep because of all the noise that the deers were causing.

The inhabitants of the decoy house woke up in anger and came out to chase away whatever was causing the noise. This made them clash with the herd of deer, who were also irritable. Thus, a great fight ensued. 

He and Ruff watched all of these happen from a distance with amusement. Arthur, in particular, laughed when he heard someone shout in anger, "Where did these abominable creatures come from?"

Then he went to the backyard to skin and butcher the deer. After a year of experience killing and butchering sheep, he has become very skilled in the art. 

By morning, he was done cutting up the deer. He even had time to salt and roast it. Only then was he ready to leave his mother's house.