Plane of Water

The Plane of Water is a vast realm of deep mysteries, shadowed darkness, and wondrous life, all combined into one of the most recog-nizable elements across the multiverse. Life flourishes in this plane, which many travelers can relate to on some level – after all, most Material Plane worlds have seas and oceans, so it’s too hard to imagine a vast, endless version of it.
But the Plane of Water holds so much more, and it is one of the most hospitable of the Inner Planes to natural life (second only to the Plane of Air). With a little magic, travelers can dive into the Sea of Worlds and seek out the wonders and treasures of the Great Coral Forest or the wrecks of lost ships in the Graveyard of Sails. Deeper still lies dangerous lairs of cold, unyielding monsters, such as the Fathomless Caves and the Trench of Death.
While most of the planar activity is underwater, contrary to most beliefs, the Plane of Water has a surface, and this surface is broken by several islands. The most famous of these islands is the Isle of Dread, surrounded by a fierce storm that extends to many Material Planes, which has the capability to draw in ships and strand them. The island itself is a dangerous, jungle-filled wilderness with great dinosaurs competing for food.
The treasures and sites of the Plane of Water are there for travelers willing to brave the monsters and dangers of an endless sea of unrelenting change.

Geography

LAY OF THE LAND

The Plane of Water has three major layers to its endless geography and two side regions where it borders other Inner Planes. The first is actually above the waters of the Sea of Worlds, where a sun and stars sit similar to most Material Planes. Ships that inadvertently travel through a portal to this Inner Plane can drift forever on the waves, though it is more likely they run afoul of one of the many terrible storms that rocks the region. This elemental realm is a plane of constant change, with seas shifting dramatically from calm to stormy in the blink of an eye.
Islands comprised of rock, earth, and even coral break the surface of the Sea of Worlds, though few are permanent. The nature of the watery plane breaks down hard surfaces, eroding them and sending them back to the depths. Few things last above the sea, as super storms are known to suddenly appear without warning to drag everything back down. There are no native creatures that do not swim in the Plane of Water, though swarms of winged quippers break the surface of the sea to ride the stormy winds.
The upper region of underwater is known as the Sea of Light. Here, much of the sunlight from above the sea filters down, creating a brightly lit aquatic wonderland. Great swaths of coral reefs clinging to unanchored rocks dot the Sea of Light, and within these are found the fortresses, strongholds, and cities of the most common planar natives, including the merfolk and merrow.
Even at night, the Sea of Light is illuminated, bathed by a soft green light that seems to infuse the water. The water temperature is near perfection at all times, not too hot and not too cold, though pockets of intense heat, slime, and chill float through the currents. Throughout the waters, “up” is considered to be towards the surface of the Sea of Worlds, while “down” is considered away from the light. In all por-tions of the Plane of Water below the surface, however, it can be difficult to easily determine “up” from “down” especially since the effects of gravity are lessened in the water.
The deepest sections of the Plane of Water are reserved for a lightless realm known as the Darkened Depths. It is here dwell the greatest and most monstrous of creatures, including elder krakens and the lairs of the elemental lords of water. Otonia, the Princess of Evil Water Elementals, is the best known among these primordial powers, and she is fickle and without mercy. Light from above the Sea of Worlds does not filter down to the Darkened Depths, and whatever infusion illuminates the Sea of Light above is lessened here.
The Plane of Water borders two other Inner Planes at its extreme edges. Where it borders the Plane of Air, the Sea of Worlds grows frigid and great icebergs bob slowly in the water. This is the Sea of Ice, and travelers that continue through it eventually reach the Frostfell (also known as the Plane of Ice). White dragons and remorhazes are known to lair in the icebergs of the Sea of Ice. Particularly large rogue icebergs have been known to break from this area to float into the Sea of Worlds, though the warmer waters ensure the massive ice formations don’t last forever.
At the other end, the sea grows shallower where the Plane of Water is near the Plane of Earth. This area is known as the Silt Flats before giving way to the Swamp of Oblivion (also referred to as the Plane of Ooze). In the Silt Flats, the water is thick and sludge-like, and it is not uncommon to have acidic globs float out into the Sea of Worlds to wreak havoc on all life. Unnaturally large and aggressive insects, such as mud mosquitos, are known to occupy the Silt Flats. Because of its thick, shallow water, most regular inhabitants of the Plane of Water avoid the Silt Flats, though travelers have been known to scour the region looking for lost treasure sites, such as the Mud Tombs.

Ecosystem

Highlights & Impressions

The below listings include notes on highlighting the nature of the Plane of Water as characters explore and travel through it. These are suggestions of elements that can be used in descriptions of the landscape and denizens with the goal of actualizing the “outside” nature of the multiverse beyond the Material Plane. Use them to incorporate into encounters and adventures on the Plane of Water.
Water, Water Everywhere. Below the surface of the Sea of Worlds, the Plane of Water is a vast endless ocean suffused with its own light. The brilliant azure waters are clear and pure unless tainted by some force, but there is a discernable “up” and “down” in the ocean – above the waters are lighter, and below the waters are darker. Waterbreathing creatures from other planes immediately notice the clean quality of the Plane of Water as well.
Stream of Bubbles. Bubbles of endless sizes rise up constantly from the depths of the Plane of Water, the result of any number of thousands of possibilities. These harmless effects ebb and flow to the events that have happened elsewhere on the plane, and many native creatures have legends about them. Locathah believe them to be moments of history from somewhere deeper below rising to greet the surface, while sea elves view them as warning signs.
Pull of the Current. The currents on the Plane of Water constantly pull and tug invisibly at beings in the water. They are less whimsical than the winds on the Plane of Air and more steady, though they can still shift and turn with surprising speed. Following a current is the fastest way to travel underwater, but most predators realize this as well.

Ecosystem Cycles

CYCLE OF TIME

A sun rises and sets over the Plane of Water in a regular 24-hour cycle similar to most Material Planes. It is often obscured by thick storm clouds, but when it passes in the azure sky overhead it creates light and very little heat. Some planar scholars theorize it is a massive portal to the Plane of Fire, though no definitive research has been done to prove this. Attempts to reach it have been thwarted by the unnaturally intense thunderstorms that gather.
At night, a deep blue twilight settles over the Sea of Worlds and the night sky is covered in twinkling stars. The night sees no change in temperament for the storms, unfortunately.

Localized Phenomena

HAZARDS & PHENOMENA

There are many natural hazards in the Plane of Water that can derail or end a traveler’s journey. Even the native creatures of the realm know to avoid some of these dangerous phenomena.
Hot Spot Vortices and planar pockets exist all across the multiverse, and that is no different for the Plane of Water. Sometimes, those pockets lead to a much hotter location, such as the Plane of Fire, Magma, or one of the Lower Planes. This creates a floating hot spot in the sea. A hot spot is typically a rough sphere 2d10 x 100 feet in diameter. Creatures in a hot spot suffer 5 (1d10) fire damage each round.
Ice Pocket Similar to the hot spot, an ice pocket is a supernaturally cold vortex that travels in the Plane of Water. The watery conditions are more conducive to the cold than the heat, and as such the ice pockets are large spheres 2d10 x 500 feet in diameter. Creatures in an ice pocket suffer 3 (1d6) cold damage each round and they must make a DC 14 Constitution saving throw. On a failure they suffer a level of exhaustion. Ice pockets often have floating ice chunks drifting along with the current making identification of this danger a little easier.
Powerful Current The waters of the Sea of Light and the Darkened Depths are pushed and pulled by random, chaotic forces, creating currents that act like roads. Canny planar natives learn to detect these currents and use them to get to one place or another more quickly (or to avoid them altogether if they happen to be flowing in an undesired location). The strength of a current can randomly be determined on the below table, which determines the DC for Strength (Athletics) checks to swim out of a current. Swimming directly against a current requires a Strength (Athletics) check against the listed DC made at disadvantage. You can roll on the table to also determine the size of the current as represented by the number of Strength (Athletics) checks needed to escape.
A special note is needed for the doom tide. Somewhere in the Plane of Water sweeps this massively powerful current. The doom tide shifts haphazardly, sometimes flowing in a single direction for months at a time and other times changing direction several times in an hour. Some planar scholars believe the doom tide originates from the depths of the Darkened Depths in some mysterious hole, perhaps a permanent vortex to the Plane of Air, but to date no one has found its source. The doom tide is always massive (4 checks necessary to get out).
On the random encounter tables for the Plane of Water, a current is identified as either helpful or hindering. A helpful current is one that is flowing in the direction the party is traveling, which can speed up time considerably. In this situation reduce travel time in half. On the other hand, a hindering current is one that is flowing in a different direction than the one the party wants, requiring them to pass through it or go around it. Going around a current requires more travel time - one hour for a small current, four hours for a medium current, eight hours for a large current, and sixteen hours for a massive current. Trying to swim through a current requires a number of Strength (Athletics) checks against a DC set by the current’s strength.
1d20 Current Strength DC 1-4 Light 10 5-11 Moderate 13 12-15 Strong 16 16-19 Brute 20 20 Doom Tide (see text) 25 1d10 Current Size 1-3 Small (1 check) 4-7 Medium (2 checks) 8-9 Large (3 checks) 10 Massive (4 checks) Red Tides Red tides are dangerous patches of fungi and spores that drift through the Plane of Water, causing panic and chaos where the current takes it. Native creatures know to avoid red tides with all possible haste as the consequences of being inside of one can be deadly. As rare as they are, a red tide can cover a substantial area. Each red tide fills a sphere 2d10 x 50 feet in diameter. Living creatures inside of a red tide must make a DC 15 Constitution saving throw or suffer the effects of the contagion spell, inflicting a random disease from that spell’s list of possibilities.
Slime Water Sometimes the never-ending tide of Sea of Worlds pulls large swaths of the Swamp of Oblivion away, sucking them into the sea. There, they are sometimes picked up by currents and pulled further into the sea’s depths, creating large pockets of dangerous slime water. The mud from the Swamp of Oblivion mixed with certain aspects of the Sea of Worlds creates a corrosive mixture that harms creatures caught in its path. A patch of slime water is typically a sphere 2d10 x 100 feet in diameter. Creatures in the slime water sphere suffer 4 (1d8) poison damage per round.
Whirlpool When two currents meet they form a whirlpool, which can be dangerous for travelers in the Plane of Water. If a whirlpool is encountered, roll twice on the Current Strength table to determine the overall whirlpool strength. The highest current strength DC determines the DC for Strength (Athletics) checks made to escape a whirlpool. The real danger is being buffeted by the powerful force of the currents. The strongest current level determines how much damage is dealt each round – light (1d6), moderate (2d6), strong (3d6), brute (4d6), or doom tide (5d6).
Random Encounter Tables The below tables can be used by the Dungeon Master as a source of inspiration when a party of characters is traveling around the Plane of Water.
Sea of Light 1d100 Sea of Light Encounter 01-05 Sea elf merchants 06-10 Merrow priestess and entourage 11-15 Planar traveler looking to get out 16-20 Oceanid herbalists 21-25 Sea hag and water elemental servants 26-30 Eriphyle followers 31-35 Cultists of Otonia 36-40 Merrow hunting party 41-45 Ichthys hunting party 46-50 Some electric sea worms 51-55 A hungry swarm of sea worms 56-60 A curious pod of hippocamps 61-65 Cetus with giant shark followers 66-70 Sea serpent 71-75 Red tide 76-80 Hot spot 81-85 Ice pocket 86-90 Slime water 91-95 Whirlpool 96-00 Powerful current Darkened Depths 1d100 Darkened Depths Encounter 01-05 A coven of sea hags 06-10 Hungry giant sharks 11-15 A morkoth 16-20 A horde of swarms of quippers 21-25 A hunting party of ichthys 26-30 A curious dragon turtle 31-35 A caller of the deeps 36-40 A cetus 41-45 Sea serpent 46-50 A pod of malformed krakens 51-55 Ice pocket 56-60 Slime water 61-70 Whirlpool 71-75 Red tide 76-00 Powerful Current

Tourism

GETTING THERE

There are likely more portals to the Plane of Water than any other Inner Plane (with the possible exception of the Plane of Air), though opening them can be tricky if the traveler is not prepared. Many portals are two-way, and thus opening a portal to a realm of endless water can create a real drowning hazard for the unprepared.

Permanent portals to the Plane of Water are known to exist in enchanted waterfalls, in the mouths of deep rivers, and in the lowest trenches of seas and oceans. Sudden storms on oceans can create spontaneous portals, and one such storm ravages the Isle of Dread at all times. That portal is capable of pulling in entire vessels and depositing them on the shores of the famed island, stranding the sailors on another plane of existence entirely.

Most wild portals lead to locations in the Sea of Light, or for the really dark ones to the Darkened Depths.

SURVIVING

The Plane of Water offers normal, breathable air above the water. Many sailors have passed into this Inner Plane during a freak storm and didn’t even notice a difference. Beneath the water, the greatest threat (besides monsters and natural hazards) is drowning, so traveling without the aid of magic is ill-advised. However, considering most Material Planes have their own oceans and seas, the availability of water breathing magic is generally considered high.

Unlike Material World oceans and seas, the Plane of Water applies no pressure the further down in the water a traveler swims. Also, within a hundred feet or so of the surface, things do not float up naturally. Planar scholars have theorized that since there is no recorded “bottom” to the Plane of Water, gravity has little or no application here. Above the surface, however, gravity applies normally.

TRAVELING AROUND

As long as a traveler can swim, traveling around the Plane of Water isn’t difficult, though navigating can be tricky. Some of the advanced aquatic races, such as merfolk and merrow, have developed echostones to help locate common locations. Echostones are magical devices attuned to each other, so that a merrow raiding party in the Sea of Light can use one to return to their fortress in the Great Coral Forest.

Using a mount is a common means of transportation in the Plane of Water for non-natives, and herds of seahorses and hippocamps are known to swim wild and majestic across much of the Sea of Light.

Type

Dimensional plane

Location under

Inner Planes