A tentative estimate of Styx hits needed to sink a battleship

How many Styx anti-ship missiles would it take to sink Scharnhorst, Bismarck, a Littorio-class battleship, or Yamato?

A lucky hit near a magazine could possibly sink a ship. The estimate of roughly four heavy-warhead hits per ship is explicitly offered from memory with a warning that it could be wrong.

The estimate depends on the Styx missile carrying a heavy warhead, a detail explicitly recalled from memory. One hit in a critical location near a magazine could possibly be enough. Otherwise, the suggested figure is about four missiles per ship to start sufficient fires and cause extensive damage. The number is a tentative spoken judgment, not a tested result for each named battleship.