Researchers into the occult theorize that all the worlds of the Material Plane and the planes beyond are alive. While the exact measure of life and consciousness the universe exhibits is debated, attempts to quantify this cosmic biology point toward the phenomenon of ley lines as proof.
Ley lines are conduits of magical energy that traverse all known corners of creation, serving the same function as the veins and arteries of living creatures. These conduits, connecting geographical and cosmological features both great and small, grant knowledge and power to those who tap into them.
A ley line carries raw magical energy along with psychic impressions and other ambient energy its absorbs from its surroundings. This causes ley lines to seed magical effects, subconscious thoughts, and other supernatural phenomena along their paths, and sometimes creates unusual supernatural effects.
Psychic impressions carried down ley lines can impact the cultural and psychological growth of peoples living along the path of a ley line. Such alignments can cause two civilizations separated by thousands of miles—or even separated by planar boundaries—to evolve along similar developmental paths. Towns built on opposite ends of a ley line may have identical (or sometimes mirrored) street plans and similar histories. Artists living near a ley line may unconsciously convey their ideas to other artists on other planes, creating instances of parallel design.
When a ley line penetrates planes, it can carry influences from one plane into another, making ley lines partially responsible for the appearance of tieflings and aasimars in bloodlines that had no prior history of contact with outsiders. This effect is also responsible for some of the propagation of sorcerous power, psychic powers, and other unusual magical phenomena such as haunts and loci spirits.
Like the arteries of a circulatory system, ley lines come in many different sizes. The larger a ley line, the more capacity it has to carry magical energy. The size of a given ley line can change over time, however, and may vary at different points along its length. The size of a ley line generally impacts the strength and kinds of power that can be drawn from it by spellcasters. Ley lines have an effective caster level ranging from 1 to 20 that represents the overall strength of the ley line and determines the power of effects associated with it.
A ley line’s natural state is as an imperceptible current of energy. Finding a ley line requires the use of a skill or spell that can detect the magical energy a ley line radiates.
Detect magic can locate the presence of an accessible portion of a ley line within its area of effect and uses the ley line’s effective caster level to determine its aura’s strength as if the ley line were a magic item. True seeing reveals all accessible ley lines within its area of effect—
They appear as ghostly bundles of tightly packed streams of energy. The color of a ley line is representative of its overall power level. Ley lines with a caster level of 1 are a dark violet color, while ley lines with a caster level of 20 are deep red. Ley lines with caster levels between 1 and 20 range across the color spectrum as appropriate (starting with violet and continuing to blue, green, yellow, orange, and finally red). Divination magic such as contact other plane, divination, and commune can help narrow down the location of a ley line. Additionally, legend lore can help reveal information about a known ley line. Occult skill unlocks such as dowsing can also help detect the presence of ley lines over long distances, which can be quite useful in locating an accessible portion of a ley line.
Because of ley lines’ ability to pick up ambient energy, some local effects can cause portions of a ley line to become visible. For example, in areas of wild magic, an extant ley line may manifest as a shimmering river of rainbow-hued light constantly shifting through the color spectrum, while locations with a powerful presence of negative energy might cause a ley line to appear as a tendril of darkness that bleeds an ephemeral black smoke tinged with red light.
Ley lines do not generally move from location to location. While the exact paths they take may drift over the course of millennia or eons, these changes are largely unnoticed by all but the longest-lived races. As such, the discovery of a ley line can impact a region for millennia and draw attention from those seeking to exploit the ley line’s power. Civilizations that discover ley lines sometimes mark the locations in which their power is most easily accessible by erecting monuments such as menhir circles or obelisks. These sites are typically used to perform rituals or other functions that tap into the latent power of a ley line to enhance spellcasting. A powerful wizard might build his tower atop a particularly strong ley line, a druidic sect might construct a menhir circle nearest to where a ley line touches the ground, or an ancient dragon might build its mountaintop lair as close to a ley line in the sky as possible. Accurate maps and charts depicting the paths and intersections of ley lines are reliable for centuries or more and can reveal nodes of power across worlds and planes.
While a ley line can range from hundreds to thousands of miles long or more, most portions of a ley line are only faintly visible to powerful magic, and their power is inaccessible. However, spellcasters can tap into rare sites where the power of ley lines is concentrated, or where ley lines cross, to increase their power. These sites can be of any size, ranging from a tiny cave under a great mountain to an entire mountain range.
Most of the effects generated by a ley line’s accessible portions are passive and easy to miss. Planar energy, psychic impressions, and other collected powers bleed out into the land and influence the development of local life. A creature capable of casting spells or using spell-like abilities can attempt to tap into an accessible segment of a ley line within 100 feet. Doing so takes 1 hour per 2 caster levels of the ley line and requires a Spellcraft check with a DC equal to 20 + the ley line’s caster level. Success indicates the creature is attuned to the ley line and gains a +1 bonus to its effective caster level for all spells and spell-like abilities. This bonus increases by 1 for every 5 caster levels of the ley line, to a maximum of +5. Depending on the nature of the ley line convergence, this bonus may apply only to certain spells and spell-like abilities. For instance, a ley line convergence atop a great volcano might apply its bonus only to spells and spell-like abilities with the fire descriptor. Hags or other creatures with the coven ability benef it from the bonus of ley line attunement so long as at least one member of the coven is attuned to the ley line and all coven members are within 10 feet of an attuned creature. Some ley lines also grant creatures attuned to them special abilities such as bonus spells, spell-like abilities, or other supernatural effects. Once a creature is attuned to a ley line, the bond is permanent unless dispelled. Dispel magic and similar effects can break a creature’s attunement to a ley line; the caster attempting to break the attunement must succeed at a caster level check with a DC equal to 11 + the caster level of the ley line. When an attuned creature is more than 100 feet from the ley line, it gains no benef it from the attunement, but the benef its return when it is once again in proximity.
Ley lines can become damaged over the course of time, Whether by extreme magical forces or other monumental events. Damage in this manner can cause a supernatural bruise that bleeds out into the location surrounding a ley line. Harming or destroying ley lines is difficult, given their monumental size and power. Even the weakest of ley lines are impervious to most physical and magical attacks, though great forces can exert influence over them. Mage’s disjunction can potentially destroy a ley line, though this task requires the caster to succeed at a caster level check with a DC equal to 20 + the ley line’s caster level. Doing so immediately deals 2d6 points of damage per caster level of the ley line (no saving throw) to the caster. Additionally, all creatures attuned to the ley line and able to benefit from attunement take 1d6 points of nonlethal damage per caster level of the ley line when it is destroyed. There is a 1% chance per caster level of the ley line that its destruction creates a permanent antimagic field with a radius of 100 feet per caster level of the destroyed ley line. Furthermore, the caster of mage’s disjunction who creates an antimagic field in this way must succeed at a DC 25 Will save or permanently lose all spellcasting abilities. These abilities cannot be recovered by mortal magic, not even via miracle or wish.
Pathfinder Roleplaying Game Occult Adventures © 2015, Paizo Inc.; Authors: John Bennett, Logan Bonner, Robert Brookes, Jason Bulmahn, Ross Byers, John Compton, Adam Daigle, Jim Groves, Thurston Hillman, Eric Hindley, Brandon Hodge, Ben McFarland, Erik Mona, Jason Nelson, Tom Phillips, Stephen Radney-MacFarland, Thomas M. Reid, Alex Riggs, Robert Schwalb, Mark Seifter, Russ Taylor, and Steve Townshend.