The translation of my game and gameworld from my former system into TROS have gone pretty well. But now it's time for sorcery. The TROS system is cool, but if sorcerors suddenly become that powerful, then the world will have some serious consistency problems.
SoI'll just have to do some changes.

First of all, sorcerors manipulate spirits. They draw a fire spirit from the burning regions and command it to engulf the enemy, or perhaps clutch the sword to make it red-hot. They bolster the soul (a kind a of spirit) of a wounded comrade. They strangle the very core of the soul to cripple the body. They command the earth spirits to erect a wall. They make the wind spirits carry them, etc. etc.
So, basically, magic is pretty freeform, and every spell is an NPC of sorts, which lets me do them pretty unpredictable.
Basic practice is to find a spirit and either "conquer it" and tell it what to do, or manipulate it (e.g. making it stronger or weaker).
In my former system, a hodge podge of house-rules based on swedish game, sorcery was quite insatisfactory, so I'm going in a new direction rules-wise.
My current idea is to use a second set of sorcery attributes, similar to the derived ones in the core system.



1) The sorcerors raw power. Used to force spirits to do what they don't want to and to boost or cripple them.

2) Ability to see and probe spirits, evaluate their strengths, capabilities and status.

3) The sorcerors ability to resist the strain of summoning. To keep the world consistent, you'll gain fatigue instead of losing months.

4) The sorcerors ability to communicate with spirits, making them do things without forcing them. Usually pretty easy when you want to boost them (e.g. cause a fire to flare up or to heal someone).

These will be calculated like profencies. You get a base, derived from your stats, and then you can "buy" them up using SA's. The base should be low, about 1 or 2, for an untrained and newly discovered sorcerer. A archwizard however, will probably have about 20 dice to use against a normal person WP of 4...

Now for my questions. Can anyone come up with a good way to calculate the derived attributes from the stats? Can anyone come up with any other useful derived attribute? Does anyone have any other comments?
Is it a good idea to make different sorcerors better with certain kinds of spirits?

Why don't you use the TROS derived Sorcery attributes, and just change their names/uses/etc. At least they serve as a springboard.

Mokkurkalfe wrote: Now for my questions. Can anyone come up with a good way to calculate the derived attributes from the stats? Can anyone come up with any other useful derived attribute? Does anyone have any other comments?
Is it a good idea to make different sorcerors better with certain kinds of spirits?

Interesting thoughts

I agree with your reason for "different spirit means different skill". Without it, sorcerors would be too similar.

Popularity is also something I thought of. As a sorceror grow more powerful, he can force spirit (especially smaller ones) pretty easily and will therefore become more unpopular. So a truly powerful sorceror will have the spirits against him at every turn. Not that it bothers him, really, but still.

There will probably be some kind of terrain roll from the sorcery pool to keep a spirit above it's prefered state. The prefered state is, of course, it's natural state, otherwise it wouldn't be it's natural state. So a sorceror has to put some dice from his sorcery pool every round to keep the earth spirit from turning to dirt once more.
This way, a more powerful sorceror can have five or six fire spirits flying about.

I think the binding procedure will be similar something like a TROS combat of wills. Using your sorcery pool, you'll try to attack the spirit, or another sorceror for that matter. Fighting with weird, spiritual maneuvers will ensue. So far I've come upp with:

1) Blocking. This one will prevent a sorceror from communicating with the spirit-world. Basically, the sorcerors magical hands are hand-cuffed.
2) Draw. This means you'll draw energy from a spirit. If you draw too much, it'll wither and die.
3) Bolster. Putting your own energy, or energy drawn from another spirit, into another spirit. Will cause flames to flare and souls to be revived. Useful for making trees grow up in a sec.
Bolstering one kind of spirit with another kind may have strange results.
4) Command. Taking Control of another spirit, plain and simple.
5) Break. Used to break a sorcerors Blocking or Command.
6) Resist. A spiritual parry.

Other suggestions are welcome.

This makes for some interesting situations where you don't necessarily have to Command a spirit. Instead, you could blackmail it with Weaken.
Other possibilities might be to Draw from a Life Soul and Bolster an earth spirit with it. Voila, a sentinent piece of earth!

Most spirits will already have a physical form, so the summoning part won't be necessary. No spirit may be summoned from too far away, with the exception of souls, which are a different kind of spirit. Souls are all the spirits whose natural state isn't dead matter. So far, that includes all living beings and fire (a very primitive kind of soul).
They are drawn from somewhere I haven't decided yet (The netherworld, the afterlife, hell... Any ideas?).

The personality-for-spirits thing is a good idea. I'd imagine earth spirits would have the equalent of a very high TO, but would just take the pounding until it is controlled. A fire spirit would be pretty easy to summon...If you can catch it.