Magic on the TL 3 battlefield

[Varyon]

Originally Posted by Fred Brackin

Thinking about it myself I'd use the guidance on Area Spells even though Pentagram isn't an Area Spell. It's at least a input on how other (mostly) Two-D spells work. So it's probably 12 feet up and probably not at all into the floor.

That sounds like the way to go. You could potentially argue for being able to "stack" areas to get one that goes higher or lower. Basically, the default gets you a column that is 12 feet high. Doubling the energy per square foot changes this to be 24 feet high, tripling it makes it 36 feet high, and so forth.

Originally Posted by Fred Brackin

Also, if making a chalk mark on top of a Pentagram "cuts" the design, building a wall on top of one probably does too.

Yeah, that was my thought when I referenced the "wall-pentagram-wall sandwich" - basically what you'd need to do is build the pentagram between two walls, and the attackers can take out the outer wall with magic but then needs to march troops in (or maybe throw your suggested paint bomb) to disable/destroy the pentagrams before they can use magic on the inner wall. Which may not really slow them down much...

An alternative occurs to me. One should be able to make a Pentagram by using stones of a different color (and possibly shape, if it needs to actually be a circle and some diagonal lines rather than approximating such) for a floor. What if you did this on the top of a wall, but then had stones of the same color (and shape) right below those, and continued this down all the way to the very bottom of the wall's foundation. So anywhere you cut it, it's still a pentagram design. That would probably be rather expensive, calling for a lot more precision than walls normally need, but it seems like that would render the entire wall protected. A ritual "cut" with chalk or similar would only affect that layer of stones. Then again, with part of the design exposed, the enemy could probably just walk up to the wall with a piece of chalk and "cut" each layer they can reach in a single long swipe (or just throw a paint bomb at it), so that probably wouldn't work...

Originally Posted by Fred Brackin

If you rotate a Pentagram from the horizontal to the vertical you'd probabl;y ahve to putit on the outside of the wall and the enemy could negate it with a paint bomb. Even if it worked on the top of the wall the paint bomb would work there too.

I'm probably reaching a bit with my interpretation, but it seems like magic is forbidden from affecting a Pentagram - it explicitly notes a mundane rock thrown by a magical creature cannot cross the Pentagram, and it seems like the same should be true of things propelled via magic (for example, I believe missile spells are treated as having mundane projectiles, but Fireball or Stone Missile shouldn't be able to cross a Pentagram). Taking this further, it seems like destroying the base on which the Pentagram is built via magic (using Shape Earth under it to spread it apart, say) should similarly be forbidden, meaning it extends its protection to the surface it is on. If that is the case, then you wouldn't be able to destroy the portion of the wall the Pentagram is built on with magic, protecting it. A particularly-thick wall can probably have its outer surface removed by magic, however, so long as the part with the Pentagram attached stays whole. Failing all that (or to protect a thick wall if my suggestion is accurate), you could do the same "Pentagram all the way down" scheme I suggested above here, except now it's a Pentagram all the way through. So OpFor throws paint on the wall and their war golem (or whatever) charges into it, breaking through the first layer of stones but being rebuffed by the next one (which still has an intact Pentagram).

I'm not sure if you'd need to cast Pentagram separately for each layer or if a single casting would suffice, however.