Ghost Ship6

At the beginning of each of your turns, you may decide if this ship is 'ghostly' or not. A ghostly ship ignores islands, terrain, and other ships when moving, but cannot end a move action with any part physically overlapping an island or another ship. A ghostly ship cannot ram or be rammed, pin or be pinned, board or be boarded, and cannot dock, but it may shoot and be shot at normally. A ghostly ship does not block lines of fire for other ships.

Icebreaker3

This ship ignores terrain, except icebergs, when she is given a move action (islands are not terrain). This ship can ram an iceberg as if ramming a ship. If she does, remove the iceberg from the game instead of eliminating one of this ship's masts.