The Mountain-Chasing Whip wasn't limited to use on land. In fact, as long as one could get to the seabed, it was just as effective.
As for the Chixiao Sword, it was the Emperor's Sword that enabled Emperor Gaozu to slay the serpent, declare himself emperor, and become a Primordial Ancestor of the nation. The power of this Divine Soldier lay not in its raw offensive might, but in its extremely potent abilities related to feng shui, Destiny, Dragon Veins, and the spiritual domain. Furthermore, if the 'leader of a nation and a people' wielded this sword, they could get a general sense of the state of their nation and people.
Of course, the ancients' methods for defining a nation and a people were different from modern ones, so the Chixiao Sword would occasionally give false readings.
