While the flavor text says sorcery is weak but versatile the actually effects seem pretty strong. Before posting some effects a couple observations:
While many Sorcery spells will have a low magnitude, countermagic is only on the civilized spell list. The countermagic rules are unclear on two points. First can you reactively cast countermagic to benefit another character? Secondly if a spell effecting multiple targets is countered by one target does it fail to all targets?
It takes a minimum of 3 CAs to get a multi target Sorcery spell off (1 base + 1 range +1 targets). By the time three consecutive CAs have ticked past the combat is probably well under way if not on its way to wrapping up. Sorcery allows to either 1. save a party that is in trouble or 2. mop up the opposition saving the need to run another round of combat.
The rules are unclear if difficulty and haste modifiers (pg. 31) apply to spell casting. If so it's possible to generate up to a +60% skill modifier by taking extra time and "ritually" casting a spell.
Grimoire rules are a bit of a mess. At one point the main rulebook says a starting Grimoire, for a cult not written up elsewhere, has no more than four spells. The example under how Sorcery works gives the True Malkioni grimoire as having over a dozen spells and Bardan's Book having six. Um yeah, can anybody give me a good reason why a cult with the magic rune isn't going to have a packed grimoire...
Assuming a point buy system for characteristics Int 16, Pow 15 isn't out of the question. This gives a likely starting Sorcery score of 72 (16*2 + 30 +10), and a starting manipulation score of around 61 (15 + 16 + 30).
Ok those points aside here are some fairly powerful effects a character can pull off right out of the gate.
Flying Chariot
7 Manipulation Points (+2 targets, +5 Duration)
3 Magic Points
30 CAs to cast (Ritual Cast taking 10x normal time)
Casting Bonus: + 60%
Casts Fly on a light chariot and two horses. The extra casting time is to raise effective skill to handle the high Siz of the horses. The sorcerer then rides the chariot. Simply casting fly would be more effective but sometimes you want to make a point.
Incantation of the Heros Reborn
6 Manipulation points (+3 Targets, +3 Combine)
6 Magic Points (3 manipulations + 3 extra spells)
3 CA's to cast
Casting Bonus: -30%
This spell is best cast either 1: with extra time or 2: under the influence of a +30% bonus fate spell. This spell combines
Damage Str
Damage Resistance
Enhance Dex
Enhance Siz
This spell gives a +16 Bonus (72% rounded up to 80, divided by ten and multiplied by two) to Siz, Str, and Dex and bounces any attack doing less than 8 points of damage. The DR spell rules are unclear it seems that a bounced attack "has no effect" do not past go, go not collect any CMs.
This spell gives the recipients a minimum of one extra CA. Most likely at least a 1d10 if not 1d12 damage bonus. Adds +16% to melee skills, +32% to ranged skill and increases hit point by three bands and increases strike rank by +11.
Speed
1 Manipulation point (+1 Combine)
3 Magic Points
2 CA's to cast
Casting Bonus: -10%
Combines Enhance Dex and Enhance Int. This gives the caster a minimum of two more combat actions (plus either an extra +28% or +32% to sorcery depending on how you rule about modifiers and an extra +14 or +16% to manipulation). Best uses to this spell, cast it early in combat then use the extra CA's to cast something nasty later when nobody has any remaining CAs to counterspell.
Spirit Blast
This is simply a decrease POW spell cast in spirit combat. This nukes 16 POW/HPs from the spirit but insures that you don't bring it under 1 POW / HP (you'll have to attack for that but you cant' destroy the spirit with the spell either). I suspect many spirit cults teach some Sorcery just for access to this spell (which would be useful even at lower levels).
Into the Pit
3 Manipulation point (+1 Combine, +1 Range)
4 Magic Points
3 CA's to cast
Casting Bonus: -10%
This combines Animate (earth) and Holdfast. Somewhat wonky this spell animates the ground under the target to swallow it and holdfasts the ground to the target. May not actually be a legal spell.
Shaping Metal
2 Manipulation point (+1 Combine)
3 Magic Points
2 CA's to cast
Casting Bonus: -10%
Casts form/set (metal) and animate (metal) on a piece of metal. Basically this is a coolness effect of causing metal to flow into the desired shape without the character actually having to work it (might give some bonuses depending on the GM). On the other hand this could not only melt an opponents arms and armor off them but leave the hostile fighting a T2 like mass of liquid metal.
Fly
Any version of this cast on an opponent really. As the movement is directed by the sorcerer you can simply pin a hostile facing up towards the roof/sky to take him/her out of the fight. Over fun uses of this spell involve dropping enemies, swinging them around, and holding them upside down until the pass out.
Shapechange
Normal human is Siz 12. A newt is size 1. That's a 23 size point transformation. Yeah it requires a 70% casting skill to pull it off but you can change somebody into a newt (who will, eventually, get better).
Holdfast
Holdfasting somebody to the ground if pretty clear, what I wonder is, is this spell permanent? I get the feeling that a sorcerer with both holdfast and fly has the tools needed to cause no end of mischief.
While many Sorcery spells will have a low magnitude, countermagic is only on the civilized spell list. The countermagic rules are unclear on two points. First can you reactively cast countermagic to benefit another character? Secondly if a spell effecting multiple targets is countered by one target does it fail to all targets?
It takes a minimum of 3 CAs to get a multi target Sorcery spell off (1 base + 1 range +1 targets). By the time three consecutive CAs have ticked past the combat is probably well under way if not on its way to wrapping up. Sorcery allows to either 1. save a party that is in trouble or 2. mop up the opposition saving the need to run another round of combat.
The rules are unclear if difficulty and haste modifiers (pg. 31) apply to spell casting. If so it's possible to generate up to a +60% skill modifier by taking extra time and "ritually" casting a spell.
Grimoire rules are a bit of a mess. At one point the main rulebook says a starting Grimoire, for a cult not written up elsewhere, has no more than four spells. The example under how Sorcery works gives the True Malkioni grimoire as having over a dozen spells and Bardan's Book having six. Um yeah, can anybody give me a good reason why a cult with the magic rune isn't going to have a packed grimoire...
Assuming a point buy system for characteristics Int 16, Pow 15 isn't out of the question. This gives a likely starting Sorcery score of 72 (16*2 + 30 +10), and a starting manipulation score of around 61 (15 + 16 + 30).
Ok those points aside here are some fairly powerful effects a character can pull off right out of the gate.
Flying Chariot
7 Manipulation Points (+2 targets, +5 Duration)
3 Magic Points
30 CAs to cast (Ritual Cast taking 10x normal time)
Casting Bonus: + 60%
Casts Fly on a light chariot and two horses. The extra casting time is to raise effective skill to handle the high Siz of the horses. The sorcerer then rides the chariot. Simply casting fly would be more effective but sometimes you want to make a point.
Incantation of the Heros Reborn
6 Manipulation points (+3 Targets, +3 Combine)
6 Magic Points (3 manipulations + 3 extra spells)
3 CA's to cast
Casting Bonus: -30%
This spell is best cast either 1: with extra time or 2: under the influence of a +30% bonus fate spell. This spell combines
Damage Str
Damage Resistance
Enhance Dex
Enhance Siz
This spell gives a +16 Bonus (72% rounded up to 80, divided by ten and multiplied by two) to Siz, Str, and Dex and bounces any attack doing less than 8 points of damage. The DR spell rules are unclear it seems that a bounced attack "has no effect" do not past go, go not collect any CMs.
This spell gives the recipients a minimum of one extra CA. Most likely at least a 1d10 if not 1d12 damage bonus. Adds +16% to melee skills, +32% to ranged skill and increases hit point by three bands and increases strike rank by +11.
Speed
1 Manipulation point (+1 Combine)
3 Magic Points
2 CA's to cast
Casting Bonus: -10%
Combines Enhance Dex and Enhance Int. This gives the caster a minimum of two more combat actions (plus either an extra +28% or +32% to sorcery depending on how you rule about modifiers and an extra +14 or +16% to manipulation). Best uses to this spell, cast it early in combat then use the extra CA's to cast something nasty later when nobody has any remaining CAs to counterspell.
Spirit Blast
This is simply a decrease POW spell cast in spirit combat. This nukes 16 POW/HPs from the spirit but insures that you don't bring it under 1 POW / HP (you'll have to attack for that but you cant' destroy the spirit with the spell either). I suspect many spirit cults teach some Sorcery just for access to this spell (which would be useful even at lower levels).
Into the Pit
3 Manipulation point (+1 Combine, +1 Range)
4 Magic Points
3 CA's to cast
Casting Bonus: -10%
This combines Animate (earth) and Holdfast. Somewhat wonky this spell animates the ground under the target to swallow it and holdfasts the ground to the target. May not actually be a legal spell.
Shaping Metal
2 Manipulation point (+1 Combine)
3 Magic Points
2 CA's to cast
Casting Bonus: -10%
Casts form/set (metal) and animate (metal) on a piece of metal. Basically this is a coolness effect of causing metal to flow into the desired shape without the character actually having to work it (might give some bonuses depending on the GM). On the other hand this could not only melt an opponents arms and armor off them but leave the hostile fighting a T2 like mass of liquid metal.
Fly
Any version of this cast on an opponent really. As the movement is directed by the sorcerer you can simply pin a hostile facing up towards the roof/sky to take him/her out of the fight. Over fun uses of this spell involve dropping enemies, swinging them around, and holding them upside down until the pass out.
Shapechange
Normal human is Siz 12. A newt is size 1. That's a 23 size point transformation. Yeah it requires a 70% casting skill to pull it off but you can change somebody into a newt (who will, eventually, get better).
Holdfast
Holdfasting somebody to the ground if pretty clear, what I wonder is, is this spell permanent? I get the feeling that a sorcerer with both holdfast and fly has the tools needed to cause no end of mischief.