Rhumb Line, genuine 2-player strategy game of observation and placement on a compass rose board. Officer yellow and Sailor blue stones are placed, one at a time, building and/or blocking point-scoring rhumb line combinations. The object is to out-navigate the opposition and score the most points to rule the waves. 4 same-colour stones in a radius is 10 points, an arc 20 points and a spiral 30 points.