Let them come.

The Darleys have never been beaten yet." For the next half-hour, he lay thinking about swords, and pikes, and armour, and big stones to cast down off the towers upon assailants, and then his attention was taken by one of the great black ravens, flapping its way along over the dale, and he watched it till it seemed to him to slide down toward the cliff, a quarter of a mile away.
By-and-by he saw another great bird, and thought it the same, but directly after, the first one reappeared, and he saw the pair cross in the air.
"They've got a nest, and it must be on the High Cliff.

Wonder whether I could hit one of the great thieves with a crossbow-bolt.

Be practice," he thought; "I may have to shoot at two-legged thieves." Then the absurdity of his words came to him, and he laughed aloud.
"Well, ravens have only two legs.

Rather horrible, though, to shoot at a man.