My theory has been that Bismarck was the name of a Allagan submersible warship that just happened to be white in color that operated in the area, perhaps linked to the Allag ruins on Seal Rock. The Sea Wolf legend arises from Sea Wolf ancestors being attacked by the submerged vessel, only seeing its white bulk below the waves. The Vanu Vanu were another chimera race created by the Allag who worked like slaves in an Allag instillation. One day the crew of the Bismarck rebelled against the military leadership at the base (the other whales attacking Bismarck being other Allag ships) and the Bismarck took the Vanu Vanu and escaped into the Sea of Clouds where they unloaded them on Sky Islands where they thought the Vanu Vanu would be safe.