How would a sea crawl work?
Sailing from point A to B—even with an accurate map and a skilled navigator—the characters will find more than empty ocean. The referee will make periodic checks for random encounters, perhaps a 1 in 6 chance per 5-6 mile hex through which the characters sail. Those encounters might involve aquatic or flying monsters, but they could also be sightings of other ships, land, or even a change of weather.
The referee can prepare a chart for each of these possibilities: islands along the characters' course, other ships know to sail those waters, and so forth.
When the d6 roll for a hex indicates a random encounter, the referee can roll 1d12 against this chart to determine the nature and direction of the encounter:
Depending upon weather conditions and if the characters maintain an active watch, they may be able to avoid the encounter or sail to meet it.
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