Searching for a spell: Carving the Mystic Tower

I know I saw somewhere, some time ago, a magus who was designed to accomplish Creo-ritual type spells using Perdo magic. One example was a spell called something along the lines of "Carving the Mystic Tower", which used Perdo to carve a rock hill into a or other structure, with an Intellego requisite to know where to "cut" to maintain structural integrity. This, of course, has the advantage of not inherently requiring vis. Unfortunately, I can't remember for the life of me where to find the original source for this idea, and Google has not been helpful. Does anyone recognize this/know where I can find it?

How long ago? far enough back to be a 4e concept, or from a 4e book?

Great idea. I could see a spell conjuring a below ground area akin to CtMT but hadn't considered a straight carving effect. There is probably an argument to see the spell work as Perdo or even Rego too, as both seem plausible. Structure of the caverns would need to follow the natural strengths of the surrounding material, and you'd probably see many areas where the foundations just couldn't be tunneled through without affecting the structure above.

I think it is an archmagus of flambeau or jerbiton in the Greater Alps book

One of the PbP games (Vengeance Rides a Slow Horse) did this as well: https://forum.atlas-games.com/t/halls-beneath-the-earth/4291/1.

It is indeed mentioned in Sanctuary of Ice, under Archmaga Jacinta in the Tower of Ashes. There are a few of additional notes needed for clarity; the book isn't considered canon, the spell is completely undefined, and were it defined in 5th edition, the finesse ease factor required would probably be in the 20s...

Thank you! One further question: For this sort of spell, do you think the Intellego requisite could assist with the Finesse roll?

I'd say without the intellego req the caster has no idea where they are carving. It shouldn't assist the finesse. Adding Mags might but that's not really RAW.

If the carving spell is separated from the intellego spell, and it is assumed that the carving spell won't be cast without the Intellego effect being active - how about this as the carving spell?

And then this for the Intellego effect?

Since not all dirt/earth is good for maintaining it's shape when dug, would it make sense to use a ReTe to change a large amount of dirt into solid stone? Then to tunnel it out into the inverse tower.

Of course if this is one in the mountains there would not be this problem.

Just now saw this! That looks like a really solid combination, though I'm not sure you can get away with targeting an Individual for the Intellego spell. It might need to be upped to Part.

Surely this wouldn't be possible with Perdo. Perdo makes things worse. This would be an example of Rego, like craft magic.

It also covers destruction, be that targeted controlled destruction.

I think the guidelines for Intellego state that the size of the target is immaterial. Targeting multiple targets still needs a group modifier though.

I would make the argument that because Creating the Mystic Tower doesn't require a finesse roll, unless your doing something odd or building it in a bad place, that a perdo equivalent would like wise not require a Finesse roll

Perdo Terrum
Level 45 (not a ritual)
Range: Touch, Dur: Momentary, Target: Part
Base 3, +1 For stone, +4 Size, +3 Elaborate Design

Sadly the target is part rather then individual due to the nature of perdo; but the argument can be made that one magnitude of Elaborate design could be reduced as it doesn't require the tower to be free standing; I would accept the extra magnitude for reinforcement to allow the tower to be built on/in dirt/stone rather then just stone and only require a finesse roll on odd cases (on an angle etc)

The finesse requirement isn't detailed in the spell, but it's there. If you look in the book, when it covers the art of Creo it details it. Everything created needs a finesse roll m

I wrote the effect to use simple geometric shapes to avoid caring too much about finesse rolls. Creo will give you a serviceable sword regardless of finesse roll, only a finesse botch means it's not fit for purpose. Likewise for the Perdo effect I think.
Further though a created thing only needs a finesse check if it is not a simple thing; tree, rock, etc. Given the complexity a check is still probably needed, but having the Intellego effect running at the same time should assist that roll too.