Each plane of existence has its own properties-the natural laws of its universe. By changing the traits from plane to plane, the DM can alter the shape and feel of the places the characters visit. In general, a campaign's home Material Plane is considered the default plane for the adventurers. All comparisons are made against the Material Plane, so other planes are similar to the home Material Plane unless a plane's description states otherwise. Planar traits are broken down into a number of general areas. All planes have the following traits.
_ Physical Traits: These traits set the laws of nature, including gravity and time.
_ Elemental and Energy Traits: These traits determine the dominance of particular elemental or energy forces.
_ Alignment Traits: Just as characters may be lawful neutral or chaotic good, a plane might be tied to a particular moral or ethical outlook.
_ Magic Traits: Magic works differently from plane to plane, and these traits set the boundaries for what it can and can't do. These traits usually apply to the plane as a whole, but a plane is a vast place. There may be particular locations within a plane where the rules are different, perhaps because of natural effects, godly interference, or magical localities.
The two most important natural laws set by physical traits are how gravity works and how time passes. Other physical traits set the boundaries of the plane (if it has any) and the nature of its borders. Finally, a physical trait sets the nature of matter itself, ranging from static and unchanging to random and ever-shifting.
One variable that the DM can change is gravity, ranging from heavier to lighter to absent entirely. Furthermore, the direction of gravity's pull may be unusual, and it might even change directions within the plane itself.
Normal Gravity: Most planes have gravity similar to that of the Material Plane. That is, if something weighs 10 pounds on the Material Plane, it weighs 10 pounds here as well. The usual rules for ability scores, carrying capacity, and encumbrance apply.
Heavy Gravity: The gravity of this plane is much more intense than the Material Plane. As a result, Balance, Climb, Jump, Ride, Swim, and Tumble checks suffer a -2 circumstance penalty, as do all attack rolls. All item weights are effectively doubled, which might affect a character's speed. Weapon ranges are halved. A character's Strength and Dexterity are not affected, but these ability scores don't let the character do as much. This limitation applies to both travelers from other planes as well as natives, though the natives know of the limitation and plan accordingly. You can double or triple the heavy gravity effect for particular planes, though they won't be popular destinations with adventurers. Characters who fall on a heavy gravity plane take 1d1o points of damage for each 10 feet fallen, to a maximum of 2odl0 points of damage.
Light Gravity: The gravity of this plane is less intense than on the Material Plane. As a result, creatures find that they can lift more, but their movements tend to be ungainly. Characters on planes with the light gravity trait suffer a -2 circumstance penalty on attack rolls and Balance, Ride, Swim, and Tumble checks. All items weigh half as much. Weapon ranges double, and characters gain a +2 circumstance bonus on Climb and Jump checks. Strength and Dexterity don't change as a result of light gravity, but what you can do with such scores does change. These advantages apply to travelers from other planes as well as natives. Falling characters on a light gravity plane take 1d4 points of damage for each 10 feet of the fall, to a maximum of 20d4 points of damage. You can choose to decrease gravity even further, doubling or tripling the effect for that particular plane.
No Gravity: Individuals in a plane without gravity merely float in space, unless other mechanisms (such as magic or force of will) are available to provide a direction for gravity's pull. An example of a plane with no gravity is the Astral Plane, where everyone gets around by simply imagining themselves moving in a particular direction.
Objective Directional Gravity: The strength of gravity is the same as on the Material Plane, but the direction is not the traditional "down" toward the ground. It may be down toward any solid object, at an angle to the plane itself, or even upward, creating a chandelierlike world where everyone has to hang on or be thrown out into the void. In addition, objective directional gravity may change from place to place. The direction of "down" may vary, so individuals may suddenly find themselves falling upward (similar to the reverse gravity spell) or walking up walls. Travelers on planes with objective directional gravity tend to be cautious. No one wants to discover the hard way that the 100-foot corridor ahead has become a 100-footdeep pit.
Subjective Directional Gravity: The strength of gravity is the same, but each individual chooses the direction of gravity's pull. Such a plane has no gravity for unattended objects and nonsentient creatures. This can be very disorienting to the newcomer, but is common on "weightless" planes such as the Plane of Air. Characters can move normally on a solid surface by imagining "down" near their feet. For pockets of matter in the Elemental Plane of Air, this is the most common way to generate one's own gravity. If suspended in midair, a character "flies" by merely choosing a "down" direction and "falling" that way. Under such a procedure, an individual "falls" 150 feet in the first round and 300 feet in each succeeding round. Movement is straight-line only. In order to "stop," one has to slow one's movement by changing the designated down direction (again, moving 150 feet in the new direction in the first round and 300 feet per round thereafter). It takes a Wisdom check (DC 16) to set a new direction of gravity as a free action; this check can be made once per round. Any character failing Wisdom checks in successive rounds receives a +6 bonus on any subsequent checks until he or she succeeds.
On planes with the no gravity trait or either of the directional gravity traits, combat can be more complex, because attackers can come from above or below as well as from the lateral directions. The face statistic now operates in a third dimension, and this third figure is usually roughly equal to the height of the creature. For a Small or Medium-size target, this means a 5-foot-by-5- foot-by-5-foot face in a three-dimensional combat. On a twodimensional surface, such a target could be attacked by eight by eight adjacent opponents (one attacking along each side of a 5- foot square and one attacking from each corner). In a threedimensional combat situation, no less than twenty-six Small or Medium-size opponents could attack a single target of the same size. Eight would be adjacent at the same vertical level, nine could attack from positions above, and nine from below. For more information on face and creature sizes, see Big and Little Creatures in Combat in Chapter 8 of the Player's Handbook, and Movement and Position in Chapter 3 of the DUNGEON MASTER's Guide.
The rate of time's passage can vary among different planes, though it remains constant within any particular plane. Time becomes interesting when one moves from plane to plane, but it still moves at the same apparent rate for the traveler. In other words, time is always subjective for the viewer. If someone is magically frozen in place for a year, at the end of that time he or she thinks mere seconds have passed. But to everyone else, a year has elapsed. The same subjectivity applies to various planes. Travelers may discover that they'll pick up or lose time while moving among the planes, but from their point of view, time always passes naturally.
Normal Time: This is the standard rate of time, compared to the Material Plane. One hour on a plane with normal time equals one hour on the Material Plane.
Flowing Time: On some planes, time can flow faster or slower. One may travel to another plane, spend a year there, then return to the Material Plane to find that only six seconds have elapsed. Everything on that native plane is only a few seconds older. But for that traveler and the items, spells, and effects working on him, that year away was entirely real. When designating how time works on planes with flowing time, put the Material Plane's flow of time first, followed by the same flow in the other plane. For the example above, it would be 1 round = 1 year. For every year on the other plane, one 6-second round has elapsed on the Material Plane. The clever and the unscrupulous can abuse planes that have flowing time. The ability to step into a slower time flow for the purpose of healing and regaining spells is an effective weapon against others. You'll be back, completely refreshed, before your foes even know you're gone. Throwing opponents into a plane with a faster time flow may keep them out of action for several years and make their return a problem for future generations.
Erratic Time: Some planes have time that slows down and speeds up, so an individual may lose or gain time as he moves between the two planes. For each plane with erratic time you create, generate a random table to determine the rate of time's flow. The following is provided as an example.
d% Time on Material Plane Time on Erratic Time Plane
01-10 1 day 1 round
11-40 1 day 1 hour
41-60 1 day 1 day
61-90 1 hour 1 day
91-100 1 round 1 day
You'll want to set how often (by Material Plane standards) a plane with the erratic time trait shifts, requiring a new roll of the dice. To the denizen of such a plane, time flows naturally and the shift is unnoticed. Timeless: On these planes, time still passes, but the effects of time are diminished. Those effects should be specifically defined for timeless planes. Such conditions as hunger, thirst, and aging might not be affected in a timeless dimension. By the same token, natural healing may be affected, meaning that no wounds heal except by magic. If a plane is timeless with respect to magic, any spell cast with a noninstantaneous duration is permanent until dispelled. The danger of timeless planes is that once one leaves such a plane for one where time flows normally, conditions such as hunger and aging do occur-sometimes retroactively. A character who hasn't eaten for ten years in a timeless plane might be ravenous (though not dead), and one who has been "stuck" at age twenty for fifty years might now reach age seventy in a heartbeat. Traditional tales of folklore tell of places where heroes live hundreds of years, only to crumble to dust as soon as they leave.
Within the D&D cosmology, time flows at a normal rate, and all planes have the normal time trait. Planes with the flowing time trait or the erratic time trait change the game too dramatically for most players' tastes. The only exception to this is the Astral Plane, which is a timeless plane for purposes of aging, hunger, thirst, and natural healing.
Planes come in a variety of sizes and shapes. Most planes are infinite, or at least so large that they may as well be infinite.
Infinite: These planes go on forever, though they may have finite components within them, such as spherical worlds. Or they may consist of ongoing expanses in two directions, like maps that stretch out infinitely.
Finite: Set borders and edges limit these planes. These edges may be borders with other planes or hard, finite borders such as the edge of the world or a great wall Demiplanes are often finite.
Self-Contained: Here the borders wrap in on themselves, depositing the traveler on the other side of the map. A spherical plane is an example of a self-contained, finite plane, but there can be cubes, toruses, and flat planes with magical edges that teleport the traveler to an opposite edge when he crosses them. Some demiplanes are selfcontained.
This trait measures how easily the basic nature of the plane can be changed. Some planes are responsive to sentient thought, while others can only be manipulated by extremely powerful creatures. And some planes respond to physical or magical efforts.
Alterable Morphic: These planes are the norm. Objects remain where they are (and what they are) unless affected by physical force or magic. You can build a castle, animate a statue, or grow crops in an alterable plane, changing your immediate environment as a result of tangible effort.
Static: These planes are unchanging. Visitors cannot affect living residents of the plane, nor objects that the denizens possess. Any spells that would affect those on the plane have no effect unless the plane's static trait is somehow removed or suppressed. This is similar to casting a time stop spell, but it's even harder to affect creatures or objects. Spells cast before entering a plane with the static trait remain in effect, however. Even moving an unattended object within a static plane requires a Strength check (DC 16). Particularly heavy objects may be impossible to move (see Carrying Capacity in Chapter 9 of the Player's Handbook).
Highly Morphic: On the opposite end of the spectrum are highly morphic planes, which change so frequently that it's difficult to keep a particular area stable. Such planes may react dramatically to specific spells, sentient thought, or the force of will. Others change for no reason. In the D&D cosmology, the Outer Plane of Limbo is a highly morphic plane.
Magically Morphic: Specific spells can alter the basic material of these planes. The plane of Shadow, which can be drawn elsewhere and used to duplicate other spells, is a good example of a magically morphic plane.
Divinely Morphic: Specific, unique beings (deities or similar great powers) have the ability to alter objects, creatures, and the landscape on these planes. Ordinary characters find these planes similar to alterable planes in that they may be affected by spells and physical effort. But the deities may cause these areas to change instantly and dramatically, creating great kingdoms for themselves. Divinely morphic planes are common on the Outer Planes, which is one reason deities live there.
Sentient: These planes are ones that respond to a single thought-that of the plane itself. Travelers would find the plane's landscape changing as a result of what the plane thought of the travelers, either becoming more or less hospitable depending on its reaction.
The Material Planes are made up of fundamental elements and energies. Which elements and energies those are may vary from cosmology to cosmology, but all the various universes have basic building blocks. Within the D&D cosmology, there are four basic elements and two types of energy that together make up everything. The elements are earth, air, fire, and water. The energies are positive and negative energy. The Material Plane reflects a balancing of those elements and energies; all are found here. Other planes, particularly the Inner Planes, may be dominated by one element or type of energy. Other planes may show off various aspects of these elemental traits.
Air-Dominant: Mostly open space, these planes have just a few bits of floating stone or other elements. They usually have a breathable atmosphere, though there may be clouds of acidic or toxic gas on the plane. The gravity trait for an air-dominant plane is usually either objective directional, subjective directional, or no gravity. Creatures of the earth subtype are uncomfortable on air-dominant planes because there is little or no natural earth to connect with. They suffer no actual damage, however.
Earth-Dominant: These planes are mostly solid Travelers who arrive run the risk of suffocation if they don't reach a cavern or other pocket within the earth (see Suffocation in Chapter 3 of the DUNGEON MASTER's Guide). Worse yet, individuals without the ability to burrow are entombed in the earth and must dig their way out (5 feet per turn). Earth-dominant planes normally have objective directional or subjective directional gravity. Creatures of the air subtype are uncomfortable on earth-dominant planes because these planes are tight and claustrophobic to them. But they suffer no inconvenience beyond having difficulty moving.
Fire-Dominant: These planes are composed of flames that continually burn without consuming their fuel source. Fire-dominant planes are extremely hostile to Material Plane creatures, and those without resistance or immunity to fire are soon immolated. Unprotected wood, paper, cloth, and other flammable materials catch fire almost immediately, and those wearing unprotected flammable clothing catch on fire (see Catching on Fire in Chapter 3 of the DUNGEON MASTER's Guide). In addition, individuals take 3d10 points of fire damage every round they are on a fire-dominant plane. In general, firedominant planes have normal gravity conditions. Creatures of the water subtype are extremely uncomfortable on fire-dominant planes. Those that are made of water (such as water elementals) take double damage each round. While these conditions are typical for the Elemental Plane of Fire, there are locations such as lava pools, magma rivers, and volcano springs where the circumstances are much worse. In the D&D cosmology, pans of some infernal Outer Planes are also fire-dominant, and they too have their unusually deadly locations.
Water-Dominant: These mostly liquid planes likely drown those who can't breathe water or reach a pocket of air (see The Drowning Rule in Chapter 3 of the DUNGEON MASTER's Guide). Water-dominant planes have either the no gravity trait or one of the two directional gravity traits. Creatures of the fire subtype are extremely uncomfortable on water-dominant planes. Those made of fire (such as fire elementals) take 1d10 points of damage each round.
Positive-Dominant: An abundance of life characterizes these planes. The two kinds of positive-dominant traits are minor positive-dominant and major positive-dominant. A minor positive-dominant plane is a riotous explosion of life in all its forms. Colors are brighter, fires are hotter, noises are louder, and sensations are more intense as a result of the positive energy swirling through the plane. All individuals in a positive-dominant plane gain fast healing 2 as an extraordinary ability for as long as they remain there. Major positive-dominant planes go even further. Creatures on a major positive-dominant plane must make a Fortitude saving throw (DC 15) to avoid being blinded for 10 rounds by the brilliance of the surroundings. Simply being on the plane grants fast healing 5 as an extraordinary ability. In addition, those at full hit points gain 5 additional temporary hit points per round. These temporary hit points fade 1d20 rounds after the creature leaves the major positive-dominant plane. However, a creature must make a Fortitude save (DC 20) each round that its temporary hit points exceed its normal hit point total. Failing the saving throw results in the creature exploding in a riot of energy, killing it. The positive energy protection spell prevents its target from receiving the fast healing extraordinary ability, risking blindness, or receiving the temporary hit points while on a positive-dominant plane.
Negative-Dominant: These planes are vast, empty reaches that suck the life out of travelers who cross them. They tend to be lonely, haunted planes, drained of color and filled with winds bearing the soft moans of those who died within them. As with positive-dominant planes, negative- dominant planes can be either minor or major. On minor negative-dominant planes, living creatures take 1d6 points of damage per round. At 0 hit points or less, they crumble into ash. Major negative-dominant planes are even more severe. Each round, those within must make a Fortitude save (DC 25) or gain a negative level. A creature whose negative levels equal its current levels or Hit Dice is slain, becoming a wraith. The negative energy protection spell protects a traveler from the damage and energy drains of negative-dominant planes.
Certain planes, in particular the divine planes, have alignments just as characters do. Most of the inhabitants of these planes also have that particular alignment, even powerful creatures such as deities. In addition, creatures of alignments contrary to the plane have a tougher time dealing with its natives and situations. How a plane develops an alignment trait is a chickenand- egg situation. Certain planes are predisposed to particular alignments, so creatures of those alignments tend to settle there. This makes the planes even more disposed to that alignment, and so on. In the D&D cosmology, all but one of the Outer Planes have predispositions to certain alignments. That does not have to be true for "home of the deities" planes you create. The alignment trait of a plane affects social interactions there. Characters who follow alignments other than most of the inhabitants may find life more difficult. Alignment traits have multiple components. First are the moral (good or evil) and ethical (lawful or chaotic) components; a plane can have either a moral component, an ethical component, or one of each. Second, the trait describes whether each moral or ethical component is mildly or strongly applied.
Good-Aligned/Evil-Aligned: These planes have chosen a side in the battle of good versus evil. A universe that regularly pits angels against devils probably has goodaligned and evil-aligned planes.
Law-Aligned/Chaos-Aligned: Law versus chaos is the key struggle for these planes. A cosmology that pits armies of devils against hordes of demons has law-aligned and chaos-aligned planes. It's likely that the alignment trait for some planes has two components: one moral and one ethical. There are law-aligned, good-aligned planes, and chaos-aligned, evilaligned planes, for example. But there aren't good-aligned, evil-aligned planes (opposing moral components) or lawaligned, chaos-aligned planes (opposing ethical components). Each part of the alignment trait gets a descriptor, mildly or strongly, to show how powerful the tug of alignment is on the plane. A plane could be mildly good-aligned, strongly chaos-aligned, for example.
Mildly Aligned: Creatures who have an alignment opposite a mild alignment of a plane suffer a -2 circumstance penalty on all Charisma-based checks. Evil characters on a mildly good-aligned plane, for example, have a hard time getting along with the natives. Whether a character is lawful, neutral, or chaotic wouldn't matter for such a plane-only good, neutral, or evil.
Strongly Aligned: These planes apply the -2 circumstance penalty to all creatures not of the plane's alignment. In other words, neutral characters suffer the penalty too. A strongly good-aligned, strongly law-aligned plane would apply the penalty to creatures with a neutral aspect to their alignment (as well as to evil or chaotic creatures). The circumstance penalty on strongly aligned planes covers more situations, too. The -2 penalty affects all Intelligence-, Wisdom-, and Charisma-based checks. It's as if the plane itself was standing in your way. The penalties for the moral and ethical components of the alignment trait do stack. A neutral evil character on a mildly good-aligned, strongly chaos-aligned plane would suffer a -2 penalty on Charisma-based checks for being evil on a mildly good plane, and another -2 penalty on Intelligence-, Wisdom-, and Charisma-based checks for being neutral on a strongly chaos-aligned plane. Such a character would have a -4 circumstance penalty on Charisma-based checks and a -2 circumstance penalty on Intelligence- and Wisdom-based checks. Neutral-Aligned: A mildly neutral-aligned plane does not apply a circumstance penalty to anyone. Such a plane could become a gathering point where those of different alignments could meet, or the prize that extraplanar forces fight over. A strongly neutral-aligned plane stands in opposition to good, evil, law, and chaos. Such a plane may be more concerned with the balance of the alignments than with accommodating and accepting alternate points of view. Strongly neutral-aligned planes apply the -2 circumstance penalty to any creature that isn't neutral. The penalty is applied twice (once for law/chaos, and once for good/evil), so neutral good, neutral evil, lawful neutral, and chaotic neutral creatures suffer a -2 penalty and lawful good, chaotic good, chaotic evil, and lawful evil creatures suffer a -4 penalty. Material Planes are usually mildly neutral-aligned, though they may contain high concentrations of evil or good, law or chaos in places. This often makes the Material Plane a battleground for the various aligned planes and their natives, who may try to change the alignment trait of the Material Plane itself.
The magic trait tells how a plane handles spells and supernatural abilities. As with other traits, the magic trait describes how magic works compared to how it works on the Material Plane. Particular locations on a plane (such as those under the direct control of deities) may be pockets where a different magic trait applies. Normal Magic: This magic trait means that all the spells and supernatural abilities function as written.
Dead Magic: These planes have no magic at all. A plane with the dead magic trait functions in all respects like an antimagic field spell. Divination spells cannot detect subjects within a dead magic plane, nor can a spellcaster use teleport or another spell to move in or out. The only exception to the "no magic" rule is permanent planar portals, which still function normally. Spellcasters on a dead magic plane feel immediately uncomfortable and experience mild headaches.
Wild Magic: Spells and spell-like abilities function in wildly different and sometimes dangerous ways on planes with the wild magic trait. Any spell or spell-like ability used on a wild magic plane has a chance to go awry. The caster must make a level check (DC 15 + the attempted spell level) for the spell to function normally. For spelllike abilities, use the caster level for the ability to determine the DC and the level or HD of the creature for making the level check. Failure means something strange happens. When you create a plane with the wild magic trait, you also need a table to determine how spells and spell-like abilities are twisted by the nature of the plane. A typical wild magic table is shown at right. In addition, wild magic planes may have particular modifications to the wild magic level check according to the school or descriptor of the spell (adding +4 to the DC for necromancy spells, or -2 to the DC for good spells).
Impeded Magic: Particular spells and spell-like abilities are more difficult to cast on these planes, often because the nature of the plane interferes with the spell. Fireball spells may be cast on the Elemental Plane of Water, but the opposing natures of the spell and the plane makes it difficult. When you create a plane with the impeded magic trait, make a list of which spells are so impeded. Impeded magic planes may stop spells based on their school, subschool, descriptors, or level. Individual spells are rarely impeded on a planewide basis, but they may be impeded on a demiplane or in the kingdom of a deity. To cast an impeded spell, the caster must make a Spellcraft check (DC 15 + the level of the spell). If the check fails, the spell does not function but is still lost as a prepared spell or spell slot. If the check succeeds, the spell functions normally.
Enhanced Magic: Particular spells and spell-like abilities are easier to use or more powerful in effect on these planes than they are on the Material Plane. When you create a plane with the enhanced magic trait, make a list of which spells are enhanced. Just as with impeded magic planes, such a list is usually based on the spells' school, subschool, descriptors, or level. Natives of a plane with the enhanced magic trait are aware of which spells and spell-like abilities are enhanced, but planar travelers may have to discover this on their own. If a spell is enhanced, certain metamagic feats can be applied to it without changing the spell slot required or casting time. Spellcasters on that plane are considered to have that feat for the purpose of applying it to that spell. Spellcasters native to the plane must earn the feat normally if they want to use it on other planes as well. For example, spells with the fire descriptor are maximized and enlarged on the Elemental Plane of Fire. Wizards can prepare maximized, enlarged versions of their fire spells even if they don't have the Maximize Spell and Enlarge Spell feats, and they use the same spell slots they would to cast these spells normally (not maximized or enlarged) on the Material Plane. Sorcerers can cast maximized, enlarged fire spells without using higher-level slots, and it takes them no extra time to do so. Limited Magic: These planes only permit spells and spell-like abilities from certain schools, subschools, descriptors, or levels to be cast. Other spells and spell-like abilities simply don't work; for them, this plane functions like a dead magic plane.