Possible Clues:

• Type of battleship
• Early 20th-century battleship
• Revolutionary British battleship (1906) — first British nuclear-powered submarine (1963)
• Warship leaders of English and Danish navies used in period of low water
• Early twenieth century battleship
• Be afraid of a duck floating on the water
• A thunder god's terrible craft
• (Class of) battleship launched in 1906
• Old battleship
• Early 20th-century class of battleship