Arcane Grove

[Ruethgar]

So I wanted to make a magical site, drawing power into a circle of trees, channeled through crystals growing from the trees and releasing it to grant immense power. So, let's keep it to the rules as much as able. Energy Transformation Fields for Extended Lore of the Gods and Legend Lore of the location to basically grant knowledge of why the site was built and feel a touch of connection to the world at large with your knowledge gained.

Now actually granting magical power, that's a bit tricky. You could get Divine Rank to make petitioners using it your familiars for Imbue Familiar With Spell Ability, but if you're going that far why not just grant spells directly? So dial it back. Let's see, Imbue With Spell Ability is kinda meh with the severe limitations, but will keep it in mind. Heroics can grant access to spells via Martial Study and Martial Stance and the Arcane Swordsage, the selection is significantly more than Imbue With Spell Ability, but it feels off having martials be more adept at gaining magic than casters.

If you fudged it a little, you could Imbue Familiar With Spell Ability to another familiar, such as an Item Familiar. Would be a bit of an extra requirement to use the site, but that could work well enough. If you wanted to be more accurate, you could channel touch spell through your familiar so the spell's language is still accurate, but then you would have to work a familiar into the site. Sculpt Self should be able to apply the Spellpool feature to your familiar letting them draw different spells each time.

One of the ETFs could be for Focal Stone (http://archive.wizards.com/default.asp?x=dnd/wn/20040225a), salt can technically be considered a gemstone(worth it's weight in gold so obviously a precious mineral crystal) so Wall of Salt can make it, also potentially Create Element:Earth, or just a spell side effect for a more guaranteed gemstone creation. That would cover magic crystal. Because of the Mind Mage's existence, Wish can be a 1st level spell, make it Sanctum for 0 and you can have a pretty cheap Focal Stone. While Focal Stone requires XP, it it not a component and you are not the one casting, so it is technically fine for ETF. Where it's getting the XP would be a mystery, but that's not your problem.

The more I think about it the less enthused I get, but I still want to save what I have here and share for anyone interested in something similar.

[ExLibrisMortis]

If you have crystals already, how about using the soul crystal power to hand out some, well, soul crystals with interesting powers? You have to preserve them (in quintessence, usually), but that's part of the fun.

[Ruethgar]

Seems like a good option as an alternative. Would be interesting if you could make it into a creature and fill it back up with Bestow Power.

[Palanan]

Originally Posted by Ruethgar
Because of the Mind Mage's existence, Wish can be a 1st level spell, make it Sanctum for 0 and you can have a pretty cheap Focal Stone.

You lost me here, but something tells me Wish as a cantrip is verging on some heavy gouda.

[ExLibrisMortis]

Seems like a good option as an alternative. Would be interesting if you could make it into a creature and fill it back up with Bestow Power.
You could use some psionic circuitry (http://archive.wizards.com/default.asp?x=dnd/psm/20031225a) scribed onto some "technically a creature" trees of the grove--maybe they're intelligent psionic items. You'd want a circuit of soul crystal linked to a capacitor, an inducer, and probably a fuse and circuit breaker for good measure.

A capacitor recharges at a rate of 1 pp/day. That power point reduces the tree's available pp total for that day, but since we don't want the trees to manifest anything, that's fine (we can put in a transducer to funnel excess pp into the capacitors, if needed). A visitor to the grove activates the tattoo by performing a ritual that activates the inducer component.

The only problem you have at that point is that you need a massive number of capacitors if you want to provide multiple soul crystals daily, and that you need to give the trees the ability to manifest a bunch of different powers (else they can't put them a soul crystal). You basically want your trees to have manifesting ability, ML 17, the right ability score at 17, and a tiny power point reserve, and then apply a ton of psychic chirurgery. Afterwards, you can feeblemind the tree or something (using greater humanoid essence to make it vulnerable). You end up with a tree that's not very much different from a regular tree, but still produces soul crystals if the right rituals are performed. Though technically, the ability to manifest powers (let alone ML 17) is not an intelligent item power that's in the DMG, so this relies on a little homebrew (you could always break out fusion + astral seed, but that's like taking a 16' gun to a rabbit hunt).

You might be able to use tattoos of affinity field and bestow power appropriately linked to inducer and transducer components to set up a loop, with the only action the trees have to take being "funnel all pp into recharging this capacitor". That would be pretty cool.

[Ruethgar]

Mind Mage can lower spell levels upon cast(minimum 1st level spell) at 8 power points per level. From there you can typically find a way for the spell to be caught and used such as a Spellhoarding dragon making an instant scale scroll of it for StP Erudites and Wizards to drool over and copy or for Sorcerers to become familiar with.

Your mentioned psionics reminds me that in the Dark Sun setting they have Life Shaped creatures who could easily be built as trees and gain some powers. ML 17 is a bit much for them though. I suppose easier and more 1st party would be to psychic sandwich some of your followers into trees. Bestow Greater Curse or Permanency should be reasonable for Tree Shape if you wanted it a little more dispelable. Little constructs, bogons, or similar may be in order as well. If homebrew is allowed, Gramarie could make that quick and easy.

Edit: I'd never really read up on psionic circuitry before, but the trees should be able to Psycarnum Infusion+Azure Talent a Transducer to fully charge a Capacitor in a few minutes even for the more expensive possible uses. Looks like the trees only need 13 ML to be able to pull it off, but that's still rather significant.

You know, I'm not actually seeing a requirement that the psionic tattoos be put on a creature, just that it be applied to skin.

Animal Friends x5 advance your little monkeys to 2 HD then Chain Awaken. Have them take Extra Familiar twice and Construct Familiar once and Spell Trap them to double Familiar Form and Incarnate. Rebuild and drain their HD away so they are ECL-6. From there, that's a free 7 levels, include a Major Bloodline in there for 3 more ML, then you just have to get them up 3 more ML. Taking them as followers with their ECL taken as their level, you can go for a total 12 levels of Psychic Adept to reach the ML you need for the soul crystals. At that point you can psychic sandwich them into a tree or whatever.