only thing I might add..from waay too much Discovery Channel, etc., most of the worlds' ocean floor appears to be a bit on the muddy side. You might want to make snowshoes or something, 'cause I don't know how far it would sink into it, 'cause it looks heavy..;)
otoh..you could make it a planetary explorer for space..excellent in all other respects..

I wish I'd said that.. The Staircase Wit

anahl nathrak uth vas betude doth yel dyenvey..;)