Submarine (Civ1)

The Submarine has a visibility range of two sea squares. Invisible to land units, can be spotted only when adjacent to a sea or an air unit (not when two spaces away). Can't attack land.
== Civilopedia entry ==
The Submarine is a submersible warship, designed to attack other ships from underwater by firing torpedoes. Although weak on defense, the Submarine is a feared offensive weapon due to its ability to attack while hidden. Often a torpedo striking a ship is the first warning that a Submarine is nearby. A lurking Submarine can hide near the sea lanes and then strike out at a passing Transport, Carrier, or other ship.