Little bit of lore on the Lunar Whale, since so many people have said they don't know about it, and it's ugly etc.
It's originally from Final Fantasy IV, and it was originally called the 魔導船 or Madōsen == Magic Ship. It was created by a Lunarian who is significant to the plot of FFIV. He hid in the ocean in the bay of a continent that's somewhat shaped like a serpent or dragon. It was specifically used by said Lunarian to travel from the Red Moon to Earth. The Lunarians were a highly advanced society with advanced lifespans, magic, and crystals who were originally from the fifth planet of the solar system. An unexplained calamity struck their planet, destroying it, causing them to escape on a red asteroid similar in shape to our normal moon. Knowing the blue planet to be habitable, they set their moon into a stable orbit, and put all of their citizens into a preservative hibernation, as it was largely agreed upon that they should wait until the Earthlings had evolved enough to co-exist peacefully with them before they could colonize parts of Earth.
One among their number wasn't content to wait, and wanted to wipe out humanity so that the Lunarians could inhabit the Earth right away. He constructed the Tower and Giant of Babil, but was forced into slumber by the only other Lunarians who were not in hibernation, and then sealed into that slumber by a set of crystals of Light and Dark. The two Lunarians that sealed him away were brothers, and the younger of the two constructed the Lunar Whale in order to travel to Earth to try and speed up humanity's evolution by teaching the arts of airship craft and magic to mankind. For this gift, he was murdered by the some of the same people he taught magic to, and his spirit was sealed inside of a mountain.
The Lunar Whale itself was his ship, and it is used in game to travel to and from the moon. It is also used in the After Years phone game sequel to bring a specific character back to Earth. It was made in the shape of a whale, so that it could sit underwater in disguise while its owner traveled abroad (supposition).