leviathan has the same characteristics, as the others Esper in all FF... look always with a sharp snout and skin rough and scaly.... The Sea Serpent in LL cutscene look more similiar to this: http://finalfantasy.wikia.com/wiki/S...al_Fantasy_III)

Leviathan is a Sea Dragon, LL cutscene is more a sea serpent ^^

(and everything if fall in the sea, if it's big, can make a tsunami... not only leviathan :x )