Invisible lines of power crisscross the land, waiting for a suitably skilled arcane spellcaster to tap their amazing power. Unlock the secrets of ley lines for your 5E campaign.
(Note: These rules are designed to be used with the Aetaltan glyph casting rules.)
Ley lines are similar to essence wells in that they represent a place where there is more essence available than one sees normally, but unlike essence wells, which exist on our plane of existence, a ley line’s essence flows through the essential plane. This makes ley lines more difficult to find, and it requires extra effort to tap their power. In addition, where essence wells are a stationary phenomenon, ley lines may change their course.
Each ley line has a power level from 1 to 10 that indicates its strength. Ley lines are indicated in Aetaltis products by giving the ley line type followed by the power level in parentheses, like this: Lesser Ley Line (1). This number represents the ley line’s maximum power level. (See Varying Power Levels below.)
The power level of a ley line is a game mechanic and not something the people of Aetaltis think about. Rather, if a spellcaster on Aetaltis is talking about a ley line, they’ll refer to it by its type.
Minor Ley Line
Minor ley lines are the most common type. They are fickle, often changing position, but useful to wizards if they can spot one. Finding a minor ley line is, like catching a good breeze while sailing, a mix of skill and luck.
Lesser Ley Line
Lesser ley lines are far less common than minor ley lines. Their courses are equally unstable, but when they change position they tend to do so slowly. Wizards will sometimes build their towers in areas where lesser ley lines are known to appear. Minor ley lines and other lesser ley lines will often branch off from lesser ley lines.
Greater Ley Line
Very few ley lines of this power are known to exist. Most only reach this level of power at particular times of year or during a specific celestial event. The rest of the year they function as lesser or even minor ley lines. Greater ley lines run through the land like arteries of power, with lesser lines branching off from them. Greater ley lines are slow to move, and wizards will often build towers in their paths.
Size and Shape
Ley lines are like rivers of essence running through the essential plane. Their shape is roughly cylindrical with a diameter of five to ten yards. They typically run for many miles, often twisting and sometimes branching off into lower powered lines.
Some ley lines have reliable courses, but others shift and change their path over time. The speed of shift depends on the potential power of the line. The more powerful the line, the slower it changes course. Where a greater ley line might change its course almost imperceptibly over the course of a year, a minor line might suddenly shift to a position miles away with little or no warning.
All ley lines do not run conveniently along the ground. They may follow paths high in the sky, dive beneath the earth, plunge through a mountain, or spiral beneath the sea.
Varying Levels of Power
The power of ley lines wax and wane based on a variety of triggers. The most common triggers are the phases of Numos, the moon. Planetary alignment, comets, meteor showers, and other celestial phenomenon are also known to cause changes in the power level of many ley lines.
Ley Line Junctions
Ley lines don’t often cross, but when they do it intensifies the power of the ley lines at that junction. The power level at the point where two ley lines cross is equal to half the weakest line’s current power level (rounded up) added to the current power level of the strongest line. If more than two lines cross, add half the power level of any weaker lines (rounded up) to the strongest line’s level.
On the first full moon of the year, a lesser ley line (2) and a minor ley line (1) cross above a waterfall in the deep woods outside of Thornwall. During the time of the conjunction, both lines are at their maximum power level. The power level at the point where they cross is 2 (the more powerful line’s power) + 1 (half of the minor ley line’s power level of 1, rounded up) for a combined power level of 3.
Ley junctions are locations of great significance to Aetaltans. This is especially true if the crossing lines are persistent rather than migrating or when one can reliably predict the time and place of the conjunction. It is said that the tower of Winterkeep is built on a particularly powerful junction, where two greater ley lines and a lesser ley line cross.
Accessing a Ley Line’s Power
The true value of a ley line to an adventurer is the essence it contains. By tapping into a ley line, spellcasters can enhance spells, power ongoing magical effects, or recharge essence crystals.
Locating Ley Lines
Ley lines are uncommon enough that you aren’t likely to stumble across one by chance. Normally you need to know where to look. Some of the ways adventurers are known to have found ley lines in the past is by poring over ancient fey maps, discovering a chain of ruined holy sites that hint at the line’s presence, or observing repeated magical phenomenon in a particular area.
Sensing Ley Lines
Spellcasters can sense a ley line the same way they sense auras1. The sense a ley line, make a DC 20 magical Perception check1 (passive or active). The roll is positively modified by the power of the ley line. On a success, you sense the presence, location, power, and path of the line. If you move more than a few feet, you must make a new check to sense the ley line.
Seeing Ley Lines
To see a ley line, a character needs a way to view the essential plane. This is typically accomplished using Essential Sight1 or by travelling to the essential plane. When viewing ley lines in the essential plane they appear as glowing, patterned tunnels of multi-colored light flowing like magical rivers. The more powerful the line, the brighter its glow.
Tapping Ley Lines
Making use of a ley line’s power requires you to tap into it, a process that creates temporary binding between your spirit and the ley line. To tap a ley line, you must first see or sense it, and you must be directly in the path of the ley line. If both these requirements are met, make a DC 15 + Ley Line’s Power Level spellcasting check. On a success, you’ve tapped the line.
Accessing the power of a ley line conjunction is handled the same way, but the full power of the conjunction is used to modify the DC. Only a single check is necessary to tap the conjunction.
Breaking the Connection
Moving more than a step or two away from the place you were standing when creating the tap will break your connection to the ley line.
If you take damage while tapped to a ley line, you must make a Constitution saving throw to maintain your connection. The DC equals 10 or half the damage you take, whichever number is higher. If you take damage from multiple sources, such as an arrow and a dragon’s breath, you make a separate saving throw for each source of damage.
If your connection is broken, all game effects from the ley line end immediately.
Game Effects of Ley Lines
Ley lines have the following game effects on characters that have tapped them.
- Essence Recovery: Characters get a bonus to essence recovery equal to the ley line’s power level.
- Spell Cost Reduction: The essence point cost of spells is reduced by the power level of the ley line. The cost is never reduced below zero.
- Low Cost Spell Difficulty: Casting spells with an essence point cost lower than the ley line’s power level is difficult due to the sheer amount of power you are tapped into. Spellcasting checks for casting these spells are made at disadvantage.
- Automatic Concentration Spells: You do not need to maintain concentration on spells that have a concentration based duration. As long as you are tapped into the ley line, the spell effect continues. You can cast multiple concentration based duration spells in this fashion and have them all active simultaneously.
Binding Spells to a Ley Line
Arcane spellcasters can bind to a ley line a concentration based spell with a modified essence point cost equal to or less than the ley line’s power level. To bind a spell to a ley line:
- Successfully tap the ley line as described above.
- Successfully cast the spell.
- Succeed at a spellcasting check with a DC equal to 15 + the modified Essence Point cost of the spell.
After the binding is complete, the spellcaster can leave the area and the spell will continue. After the binding the spellcaster has no direct control over the spell and cannot change, alter, or control it.
The spell effect will continue until:
- A spellcaster unbinds it by making a spellcasting check with a DC equal to 10 + the modified Essence Point cost of the spell.
- The ley line’s power level drops.
- The ley line moves, or in the case of a junction, if any of the ley lines move.
If any of these things happen, the spell immediately ends.
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Top Graphic Credit: Millenium Collaboration, Springel et al. (2005)