RPG Resources for Ocean Voyage

Extended travel over the ocean is an adventure in and of itself, especially in uncharted and dangerous waters. A party of heroes might encounter terrible monsters of the deep, mysterious islands haunted by sinister perils, fearsome storms, shipwreck, or disaster in a dozen different forms.

Table of Contents:

• Weather
  • Wind Strength
  • Wind Direction
• Storm Perils
• Terrain
• Traveling
• Disease
• Supernatural Dangers
• Airy Water
• Airless Water
• Dead Callm
• Maelstroms:
• Stormfire

During each day of a voyage, you should check for four things:

1. Weather
2. Navigation
3. Encounters
4. The day’s progress

If stores or supplies are running short (for example, the heroes are adrift in a small boat with no food or water), you might need to add extra steps to track successful use of the survival skill, consumption of stores, and similar tasks.

Sailing Speed: This is the multiplier used when determining the speed that a sailing ship can make given the current wind conditions. For example, a ship with a sail speed of 20 feet has a speed of 40 feet under a moderate wind. In the absence of any wind, the ship is becalmed and travels at the speed of the current. A ship that loses its sails becomes a derelict drifting with the currents. A ship in a severe wind can sail only if the captain or master succeeds on a DC 20 Profession (sailor) check. If the check fails, the ship cannot be controlled and is driven by the wind. A ship in a windstorm or gale requires a DC 30 heck to sail successfully.
Driven: A driven ship cannot sail or row but is instead driven directly downwind at a speed in feet per round equal to twice the wind speed in miles per hour. For example, in a hurricane of 90 mph winds, the ship is driven 180 feet downwind every round (or 18 miles per hour the storm persists).
Back to top

Prevailing: If the wind direction is prevailing, it means that the wind simply blows out of whichever direction it normally does given the location and the time of year. For example, a broad ocean can have seasonal trade winds—strong breezes that blow from a certain direction for months in certain latitudes, making ocean crossings relatively easy.
Sailing into the Wind: A sailing ship cannot sail directly at the wind; a ship sailing within one point of the wind (sailing northeast into a northerly wind, for example) is reduced to half the normal speed the wind strength would otherwise indicate. It’s possible to tack against the wind by alternating between northeast and northwest, and therefore slowly making progress to the north.
Back to top

Strong winds bring heavy seas, drive poorly handled vessels into danger, and can batter or sink even expertly handled ships. High winds expose ships to dangerous seas, depending on the size of the ship and the strength of the wind. Ships can roll violently, take heavy sea wash over the deck, or even risk foundering. Check to see if a ship founders due to heavy seas once per day while the ship is caught in the heavy weather.
Heavy Rolls: Ships in heavy weather can take violent rolls, rocking precipitously from side to side. Heavy rolls have the same effect as a severe list, except from round to round the high side and low side reverse, with a round of level deck in between (round 1: starboard high; round 2: even; round 3: starboard low; round 4: even; round 5: starboard high again, and so on).
Green Water: Ships in heavy seas can take green water over the bows or sides—powerful rushes of surf that wash across the deck, threatening to knock down or carry away anyone on deck.A light surge of green water lasts for 1 round and repeats every 2d4 rounds. A light surge is about 1 foot in depth.
It costs 2 squares of movement to enter a square of light green water, and the DC of Tumble checks in such a square increases by 2. Any creature that begins its turn in or enters a square of light green water must succeed on a DC 6 Strength check or Balance check, or fall prone. Characters who fall prone are washed 1d4 squares in the direction of the surge; if this would wash them over the side, they are entitled to a DC 11 Reflex save to catch themselves at the rail before going over.
A heavy surge consists of violently surging water about 4 feet in depth. It costs 4 squares of movement to enter a square of heavy surge. Tumbling is impossible in a heavy surge. Any creature that begins its turn in or enters a square of heavy surge must succeed on a DC 12 Strength check or Balance check, or fall prone. Characters who fall prone are washed 2d6 squares in the direction of the surge; if this would wash them over the side, they are entitled to a DC 17 Reflex save to catch themselves at the rail before going over.
Back to top

Terrain

Coastal Waters: Waters within 50 miles of shore count as coastal waters, even if the coast is desolate or unsettled.

Open Ocean: Waters more than 50 miles from the nearest shore are considered open ocean. The ocean is vast and desolate by any standard, and ships can go many days between encounters with other ships or dangerous sea creatures.

Well-Traveled Waters: Within 20 miles of human-settled lands and kingdoms, a steady traffic of merchant vessels and warships plies the waters between busy ports.
Back to top

Traveling

1 hour, a ship travels a distance in nautical miles equal to its speed in feet per round divided by 10. For example, a ship sailing at a speed of 30 feet per round is making 3 knots, and covers 3 nautical miles in an hour. In one day of travel, assuming the ship stops for the night (the common practice along coastlines), a ship travels a number of nautical miles equal to its speed in feet per round. A ship sailing at 30 feet per round covers 30 nautical miles in a day of sailing.
Captains in open waters, or captains sailing under bright moonlight (or otherwise not concerned with being able to see well in the dark) often sail around the clock. Sailing a full 24 hours doubles the normal distance traveled in a day of sailing, so the ship with a speed of 30 feet per round sails 60 nautical miles over a full day. Sometimes contrary winds or strong currents can prevent a ship from making progress toward its intended estimation or force it to sail in a direction other than its intended course.
Stealth and Detection in Open Water: The maximum distance at which a Spot check to detect the nearby presence of others can succeed is 4d8×10 feet. Unless a character can get above or below an opponent, there is little concealment to be found.

Navigation

Ships in strange waters can become as hopelessly lost as travelers in a featureless desert or deep forest. Keeping track of where you are and how to get to where you’re going are difficult challenges for many mariners. Setting Out: The difficulty of setting an accurate course depends on the quality of information you have about where you’re going.
The DM makes this check for you, since you don’t know for certain if you have planned an accurate course.
If you don’t have any particular destination in mind, you don’t need to set a course. As long as you keep a record of course changes and distances sailed, you won’t have trouble retracing your steps or setting a new course.
Daily Piloting: Each day of your voyage, you make a piloting check to establish your position and make the routine corrections necessary to hold to your intended course.
Failing your piloting check once is not a problem; you simply failed to establish your location for the day, but you can go back to your previous day’s established position and estimate your current position given the course and speed you think you’ve followed since. You do not become lost until you fail your piloting check on three consecutive days.
Lost at Sea: A ship’s chance to get lost depends on the navigational skills of its master, the weather, and his familiarity with the waters through which it sails.
First, you check to see if you become lost only once per day during extended voyages. (You might need to check once per hour in confined or confusing waters, such as mazelike river delta). A ship at sea is not lost until you fail your piloting check three days in a row.
As on land, a ship lost at sea moves randomly. In order to recognize that you’ve become lost, you are entitled to a Knowledge (geography) check once per day (DC 20, – 1 per day of random travel) to recognize that you are no longer certain of your direction of travel.
Setting a new course once you’ve recognized that you have become lost requires a new Knowledge (geography) course-setting check. The DC is determined normally, although you should apply the modifier for guessed at an unknown starting point as appropriate. Generally, a ship has an unknown starting point only if it has been driven by a storm or similarly deprived of any method to gauge its direction and distance of travel.
Back to top

Disease

The following diseases are often encountered in seafaring environments.

• Coral Scratch: Characters who take damage from contact with coral must make Fortitude saves or contract coral scratch. If a character contracts coral scratch, the hit point damage dealt by the exposure to coral does not heal naturally until the character recovers or is cured of coral scratch.
• Sea Rot: Usually found in the worst sort of sargasso, sea rot is caused by contact with infected creatures. When a character takes damage from sea rot, he or she must succeed on another save, or 1 point of the ability damage becomes permanent ability drain instead.
• Sea Sores: Contracted from eating or drinking food or water of poor quality, such as that found in the stores of poorly provisioned ships.
• Suntouch: Caused by heat damage in dead calm (see page 13). Characters reduced to 0 Wisdom by suntouch are rendered insane instead of comatose, acquiring an overpowering compulsion to immerse themselves in the sea and/or drink seawater.

Back to top

Supernatural Dangers

Powerful and sometimes malevolent magic lurks in the deeps of underground waters and the wide expanse of the ocean. Stormfire plays about a ship’s masts in the midst of the most terrible hurricanes, yawning maelstroms swallow ships in otherwise calm waters, and fearsome calms trap seafarers in empty watery wastes until food, water, and hope itself run out.

Avoiding Supernatural Dangers

In general, characters approaching an area plagued by one of these supernatural dangers, or in an area about to be struck by one, are entitled to a DC 20 Survival check to detect the approaching danger 1 minute before it strikes (or immediately before entering the affected area, in the case of a hazard they’re moving into).

Airy Water

Considered a boon by any air-breather who encounters it, airy water is a stretch of water that is breathable by both air-breathers and water-breathers. It is filled with streaming effervescent bubbles, and normal marine animals usually avoid it. Airy water is sometimes found in the palaces of good-aligned aquatic creatures such as merfolk, aquatic elves, or even storm giants. Even after such places are abandoned or destroyed by evil, the airy water can remain, allowing surface-dwellers to explore the submerged ruins of these places. Airy water is sometimes found in dungeon water features, offering a secret passage from one place to another to those who know the water’s secret.
Characters in airy water are subject to all the normal movement and combat penalties for being in the water— they just have no risk of drowning. Airy water is typically found in or around specific rooms or chambers and does not often occur in open water (although stories of shallow coral reefs or kelp beds filled with airy water abound).

Airless Water:

The sinister opposite of airy water, airless water is a cold, lifeless dead zone. Within a pocket of airless water, aquatic creatures cannot breathe (nor can air-breathers, for that matter). Water-breathing creatures can “hold their breath” in order to enter or pass through a mass of airless water, just as air-breathers can hold their breath to enter water.
Airless water is sometimes incorporated as defenses in submerged strongholds or as deadly traps in dungeon water features, but they are more likely to occur lying close to the ocean floor and sinking down to fill trenches, depressions, and deep places along the bottom. Pockets of airless water have a dark, slightly viscous look that can be detected by observant characters.
Back to top

Dead Calm

The terrible dead calm is a horror that terrifies even the boldest of sailors. Some portions of the ocean are cursed by evil sea gods and remain forever still and unmoving. No breeze stirs the waters, no current flows to carry a trapped vessel out of the calm. Those who enter all too often die slow, miserable deaths of starvation and madness, unable to escape from the dead calm’s grip.
Dead calms are often found in conjunction with vast sargasso mats. In a dead calm, the weather is always hot and still, without a hint of a breeze. Characters in a dead calm who take damage from heat must succeed on a DC 18 Fortitude save or contract suntouch. Dead calms are also notorious for attracting undead such as ghosts, spectres, lacedons (aquatic ghouls), and worse.
Dead calms often have the same effect as a desecrate spell (and the worst dead calms have the same effect as a desecrate spell containing an evil altar or temple, even if no such structure actually exists in the area). Regions of dead calm normally extend for 10d10 miles. Oared ships can, with some work, free themselves, but sailing ships often have to resort to exhaustive towing work or powerful magic to escape the doldrums.

Maelstroms:

Naturally occurring whirlpools are dangerous enough, but some whirlpools are supernatural maelstroms— places where portals to the Elemental Plane of Water, divine manifestations of sea deities’ power, or ancient curses have created monstrously powerful vortexes in the water.
Maelstroms come in one of four sizes: minor (10 to 40 feet in diameter), major (41 to 120 feet in diameter), greater (121 to 500 feet in diameter), and immense (501 feet to 2,000 feet in diameter). Maelstroms usually have a depth equal to their diameter.
Maelstroms are surrounded by strong feeder currents that can snare swimmers or boats far from the vortex itself, carrying them within the vortex’s grasp.
Once a swimmer or ship is sucked into the maelstrom by the currents sweeping toward it (or simply has the misfortune of falling into the vortex directly), the target endures three distinct phases of danger: trapped, battered, and ejected. Minor maelstroms can only trap and batter objects or creatures of huge size or smaller; major maelstroms can trap and batter objects or creatures of Gargantuan size, and greater or immense maelstroms can trap and batter creatures or objects of any size.
Trapped: The creature or vessel is trapped in the whirlpool, slowly being drawn down. Escaping from the trap region requires a successful Swim or Profession (sailor) check against the maelstrom’s DC, based on its size. This moves the creature to a square adjacent to the maelstrom (the current doesn’t sweep him or her back in immediately but can do so in subsequent rounds). Failing that, the creature or ship is unable to move of its own accord, and revolves helplessly in the whirlpool. At the end of a trapped character’s turn, move him or her 30 feet clockwise around the rim of the whirlpool.
Battered: At the end of trapped time, the creature or vessel sinks into the maw of the maelstrom. This takes 1 round, during which the creature or object takes the indicated damage. For ships or vehicles, every section is damaged. Creatures can take no actions in this round.
Ejected: On the next round, the maelstrom ejects the creature or vessel at its bottom. The creature or vessel is now at the bottom depth of the maelstrom. If the maelstrom has a particular exit—for example, a hole in the bottom of a lake, or a portal to the Elemental Plane of Water—the creature or vessel passes through. Otherwise it comes to rest on the bottom or is adrift in the water a short distance from the bottom of the maelstrom’s funnel (1d4×10, 20, 50, or 200 feet, depending on the maelstrom’s size). A maelstrom without an exit simply generates currents flowing away from it on the bottom with the same strength as currents flow toward it near the surface. Buoyant creatures or objects return to the surface, but there’s no reason they couldn’t be caught in the maelstrom’s grip again.

Stormfire:

In the most terrible storms and hurricanes, ships are sometimes struck by stormfire, a capricious and seemingly malevolent phenomenon that has brought more than one vessel to complete ruin. Stormfire gathers slowly, beginning as a faint green phosphorescence dancing along a vessel’s rigging and rails. In many cases it proceeds no further; it is simply a disconcerting omen but not dangerous. But sometimes (about 20% of the time) stormfire continues to gather and grow stronger, until suddenly it seems that the whole ship is wrapped in glowing green fire.
A creature entering a square containing stormfire has a 50% chance of being subjected to a brilliant emerald discharge that deals 2d6 points of electricity and 2d6 points of fire damage (Reflex DC 15 half). Stormfire manifestations usually last for no more than 2d8 rounds before guttering out, beginning in one random square on a ship’s deck and spreading to one random adjacent square each round until the manifestation ends.
Back to top