Retrograde Battleships is a variant of Battleships, where the ships given must be located within the grid.


The objective is to add ships to the grid, subject to the following rules:

  1. All given ships on the in the key must be included in the grid with no others.
  2. The grid contains possible placements for all ships, the correct locations of the ships needs shading in.
  3. No ship may touch another, even diagonally.


A standard 10x10 retrograde battleships and its solution.

Retrograde Battleships Example
Retrograde Battleships Solution