Move Terrain Math

[hoganbball23]

Background-in my campaign the Orcs are currently seiging a city that is quite far from the main dwarven army stronghold, about a two week walk. Im trying to figure out if move terrain can allow one powerful dwarf mage to carry the land and the army and all equipment, fly close to the battle and release the spell to unleash the army using Move Terrain, and how much that would cost.

The dwarf knows Move Terrain at Skill 20, therefore time 1/2 cost reduced by 2,maintenance cost reduced by 2. Magic p.8-9. Area spell cost is multiplied by the affected area.

According to various space calculations of efficiency, you can fit 3 people per square yard if planning on cramming in that many people with military efficiency. So 10,000 soldiers could fit inside 3,333 square yards.

Area=piR2 so 100 yd circle will grant 3500 square yards.

Thus, the cost 10 to cast, 8 to maintain 1 minute move terrain for a 100 yd area becomes 8 to cast, 6 to maintain 30 seconds due to skill and lasts 1 hr.

So its 800 energy to cast, 600 energy to maintain each hour after that.

So thats fine all the dwarves can hold hands and get past the initial cost of 800 while using only 3 of the casters.

My question is can the dwarves inside the Move Terrain bubble touching the bubble contribute to the maintenance cost of the spell? How would some other mages with lend energy touching the area effect that?

Basically it will still take him a day to move as far as he needs to regardless of transport method, so i need a way to modify spending 600 energy. I suppose he could just carry a ridiculous amount of manastones, but thats less fun.

Thanks all.

N.B. Dwarf has 12 FP, Magery 3.

[Anaraxes]

Based on the spell text description that magic can be cast from inside the area, automatically hitting the holder, I'd say mages inside could contribute as normal for ceremonial magic. (They could certainly cast Lend ST.) The physical barrier around the transported area seems not to be a barrier to magic.

You might want to count the shrinking and transportation as a distraction calling for Will rolls to retain concentration for the cast. (Or you could decide that since the drawing motion can't start before the spell completes, then they're not distracted until right after that spell. Being carried is evidently not particularly uncomfortable. (Which is more than I could say for being packed that closely with a bunch of armed dwarves for a couple of weeks. You're guaranteed fresh air, but that's not all their is to long-term comfort. Might want to let the army encamp normally and just pull in the area of the whole camp, also making sure they've got stored water and food in the camp -- or conjurers.)

[Refplace]

Originally Posted by hoganbball23

According to various space calculations of efficiency, you can fit 3 people per square yard if planning on cramming in that many people with military efficiency. So 10,000 soldiers could fit inside 3,333 square yards.

Area=piR2 so 100 yd circle will grant 3500 square yards.

I dont know, a tight fit for that length of time.

Originally Posted by hoganbball23

Thus, the cost 10 to cast, 8 to maintain 1 minute move terrain for a 100 yd area becomes 8 to cast, 6 to maintain 30 seconds due to skill and lasts 1 hr.

So its 800 energy to cast, 600 energy to maintain each hour after that.

Sorry,your off.
The cost reduction from skill is factored in on the total cost, so after you multiply base cost by area.
So 998 to cast, 798 to maintain. See GURPS Magic, p. 8.
It says... "Calculate the entire cost for a spell (for instance, by multiplying cost for the size of the subject or the area affected) before applying energy cost reductions for high skill."

Yes, skill reductions dont help a lot with Area spells, but if they did you could cast a spell of any size for free once you got enough skill. Think about all those weather spells!

Lend Energy or other means from the caters inside could be helpful, probably range to edge of area though so put casters at the edge.
I think your best bet is Raise Cone of Power (GURPS Thaumatology) or Mass Magic from that or Urban Magics.

[hoganbball23]

So in order to tap into the Cone of power, is there a distance penalty or do you just do it? Do you need to recast cone of power at distance penalty?

[Gnomasz]

Originally Posted by Refplace

Sorry,your off.
The cost reduction from skill is factored in on the total cost, so after you multiply base cost by area.
So 998 to cast, 798 to maintain. See GURPS Magic, p. 8.
It says... "Calculate the entire cost for a spell (for instance, by multiplying cost for the size of the subject or the area affected) before applying energy cost reductions for high skill."

This. Also, it's irrelevant, as your best bet is not Lend Energy's or anything, but Ceremonial Magic. I'd say the caught soldiers are still part of the ceremonial and can provide energy for maintenance. The spell says nothing about the sphere disturbing magic. Quite the opposite, it specifically states that mages inside can affect the caster.
The problem is, by default, all unskilled spectators can only provide 100 points of energy.

[hoganbball23]

Originally Posted by Gnomasz

This. Also, it's irrelevant, as your best bet is not Lend Energy's or anything, but Ceremonial Magic. I'd say the caught soldiers are still part of the ceremonial and can provide energy for maintenance. The spell says nothing about the sphere disturbing magic. Quite the opposite, it specifically states that mages inside can affect the caster.
The problem is, by default, all unskilled spectators can only provide 100 points of energy.

So in order to cover the 798 energy every hour for maintenance, id have 100 random soldiers covering their part, and need 698 from mages that know move terrain or from non mages that know the spell at 15 or higher. So of my 10,000 i would need 233 mages inside the dome that know the spell.

How does one know a spell at 15 or higher without being a mage?

[Anaraxes]

Originally Posted by hoganbball23

How does one know a spell at 15 or higher without being a mage?

Study, which is to say character points invested in the IQ-based skill that is the spell. Being smarter helps. You'll lack the bonus from the relevant talent (Magery). Many spells can't be learned because Magery is a prerequisite; others would be challenging to learn because Magery, while not a direct prereq, is a prereq of some spell that is a prereq of the spell you want to learn.

I wouldn't expect a lot of characters without Magery to know spells at 15. But it's not impossible.

[Gnomasz]

Originally Posted by hoganbball23

So in order to cover the 798 energy every hour for maintenance, id have 100 random soldiers covering their part, and need 698 from mages that know move terrain or from non mages that know the spell at 15 or higher. So of my 10,000 i would need 233 mages inside the dome that know the spell.

How does one know a spell at 15 or higher without being a mage?

Or you need a couple of casters who would create a couple of ceremonial circles, each transporting fewer troops, but also each giving it's caster 100 points of energy.

If you have DF 15: Henchmen, look into the notes on ceremonial magic there. Cultists (or just trained troops) could help a little, not solving the problem, but reducing the demand for ceremonial casters.

[hoganbball23]

Oh that's the ticket then!

In this world all dwarven clerics know move terrain as its given to them as part of their power investiture. Step 1: 100 clerics each cast move terrain on a 10 yd radius area holding hands with their 100 soldiers. (And now each soldier gets 3 yrds of space). Costs 100 energy but each person can just give one each hour which they recover.

Step 2: The 100 clerics walk into the 10yd radius area and the high priest casts move terrain on them, now packing a move terrain-ception with 10000 soldiers in it.

Booyah.