[3.5] Rules Variant: Location Specific Magic

[Adamantrue]

This is a completely new direction to an idea I have played around with (unsuccessfully) over the years. It isn't about nerfing spellcasters (though it probably changes game balance), instead more about providing an interesting new dimension and flavor.

The basic premise is that the "energy" needed to power a spell is dependent on a spellcaster's physical location, which serves as a limit to how high a level a spell can be cast.

There would be relatively random stretches of ground, call them "ley lines" for the sake of this, that extend all across the world. Outside these regions, only the most basic magical energies can be harnessed. Say, up to 1st or 2nd level spells can be cast.

A spellcaster that wants to cast a higher level spell needs to stand on (or hover over, as the case may be, but with a predefined limit) needs to find one of these lines, increasingly less common as you try to work with higher level spells. You'd be able to locate these "ley lines" through subtle clues in the environment (either a Spellcraft or an appropriate Knowledge check), though a Detect Ley Line spell wouldn't be unreasonable.

Ley Lines would vary in potency, ranging from the fairly common 2nd level to the increasingly rare 9th level. Some may even have biases, based on alignment or elemental subtypes. These factors would also be true on other planes, where any given Ley Line was opposed to spells of certain alignments/elements. And of course there would be true "dead zones", where even Cantrips couldn't be cast.

Note that with this idea, just because a spell can only be cast in a certain spot doesn't mean that its effects are limited to those places. You can cast Fly, then zip around far away from any Ley Lines, and your Dimension Doors can have any old destination you want within the limits of the spell.

It adds interesting new tactics, too. You can limit a spellcaster's power with an early bull rush, but fear the wizard with the tower where many Ley Lines converge. Main roads may trace over a potent Ley Line, or parallel one for a bit more safety.

There are of course more things that need to be explored. How far above/below the surface does a connection to a Ley Line extend? Do wizards, clerics, and druids really draw their power from the same source, or are there different lines for each? Can you corrupt/destroy Ley Lines, or create new ones? What should the generation method be for random locations, and how do you tweak that method when you want some in specific locations?

Thoughts?

[TravelLog]

This sounds excellent. Some thoughts:

Ley Line range: Ley lines are typically based on deep connections to the planet, so I would argue that the deeper you go, the stronger it gets. Conversely, the higher you go, the weaker it would get. I recommend an exponential formula based on the ley line's strength. Horizontally, I would operate on a similar principle.
Possible equations:
Vertical usage distance (below increases power, above decreases power)=
----->(Ley line level)^3 times 10

Horizontal usage (result is the radius of a circle with the Ley Nexus as it's center, weaker farther from the center)
----->(Ley line level)^5 times 10

Sources of Power: Druids, Clerics and Wizards would all draw power from the same source, but would channel and shape it differently. Wizards through personal power, druids through communion with nature, and clerics through divine grant. If you like, you could also have certain lines have greater affinity to one form of magic.

Corrupting Ley lines: Always an interesting variant and provides numerous plot points. Perhaps the more negative energy the Ley line is infected with, the greater danger to the user and the more unpredictable the energy drawn upon.

They should not be destroyable, but perhaps with enormous power they can be drained/siphoned or blocked (with devastating results for those trying to draw on it's power at that moment).

[Adamantrue]

Ley Line range: Ley lines are typically based on deep connections to the planet, so I would argue that the deeper you go, the stronger it gets. Conversely, the higher you go, the weaker it would get. I recommend an exponential formula based on the ley line's strength. Horizontally, I would operate on a similar principle.
Possible equations:
Vertical usage distance (below increases power, above decreases power)=
----->(Ley line level)^3 times 10

Horizontal usage (result is the radius of a circle with the Ley Nexus as it's center, weaker farther from the center)
----->(Ley line level)^5 times 10
I think I'd want to avoid any exponential formulas. While they may function right & make sense, its seems just beyond the normal scope of the game.

Sources of Power: Druids, Clerics and Wizards would all draw power from the same source, but would channel and shape it differently. Wizards through personal power, druids through communion with nature, and clerics through divine grant. If you like, you could also have certain lines have greater affinity to one form of magic.
That's a neat way to handle it. Coming up with a series of statistics, one of which would be a bias towards spellcaster type.

Corrupting Ley lines: Always an interesting variant and provides numerous plot points. Perhaps the more negative energy the Ley line is infected with, the greater danger to the user and the more unpredictable the energy drawn upon.

They should not be destroyable, but perhaps with enormous power they can be drained/siphoned or blocked (with devastating results for those trying to draw on it's power at that moment).
So, what would be the best way to handle it? Coming up with new spells that perform these tasks, or additional mechanics? I'm all for the spells, actually, as they would keep things basic enough to avoid a lot of problems.

[TravelLog]

I think new spells might help, but to be honest I think it's more appropriate to have certain spells possess a corruption factor inherent to them rather than just a "Corrupt Ley Line" spell. The general idea is that when channeled in certain ways, the user's vile nature creates a negative feedback channel within the ley line, infecting the energy involved.

Working example:

Certain spells are positive in nature (Cure Minor Wounds, Consecrate, Hymn of Praise, Sacred Haven, Bastion of Good, Rain of Roses, etc.). These spells, when used, partially purify (based on their power) a corrupt ley line when used successfully within the ley line's area of influence. There is a real risk inherent in using any spells whatsoever near an unbalanced, corrupt ley-line.

Other spells are neither positive nor negative. The vast majority of spells, even destructive ones, fall into this category. Fireball, Bigsby's Grasping Hand, Dimension Door, Rusting Grasp, Blink, Shapechange, Silence, Enlarge Person...the list goes on. These spells have no effect whatsoever on a ley line's "corruption rating".

Finally, some spells are, by their very nature, base, vile things. Their use saps life itself from their surroundings and turns their users into broken, shattered shadows of their former selves, leaving addicted, power-hungry demonic men and women in their wake. Spells of this type include Unhallow, Touch of Madness, Tasha's Hideous Laughter, Forbidden Speech, Sadism, Despoil, Consumptive Field, Power Word: Kill, Pestilence, and Flensing.

[Adamantrue]

I think simplifying it to anything that has a Good descriptor or channels positive energy, or an Evil descriptor or channels negative energy. It'd be easier than creating ever-increasing lists of which does which.

Do all "evil" spells corrupt Ley Lines? Or are some inherently "good" or "evil", working perhaps like Planar Traits? Are there Lawful & Chaotic ones? What about Elemental descriptors...should they be included as well.

Another thing I'm wondering about is Spell-like Abilities, Spell Completion Items, and Spell Trigger Items. Should they work independently of Ley Lines (perhaps making casters more item-dependent), or is their functioning limited to appropriate regions?