Limited Colleges

Cost: Variable
Limited Colleges (which replaces Basic Set p 67's One-Collage Magery) is a limitation on Magery where only spells from a limited number of colleges can be learned. Regardless of the college Recover Energy is learnable. One-Spell Magery is an even more extreme limitation.
== Cost Table ==
The cost of Limited Colleges is derived from One-College Magery (-40%) which is based on there being 15 to 30 available colleges. For different numbers of colleges it changes value. Combining both rules produces this table (green cells are given in rules, the rest are extrapolated. 
Total Colleges in setting 	2 	3 to 2	7 to 14	15 to 30	30+
One-College Magery 	(-10%)	(-20%)	(-30%) 	(-40%) 	(-60%)
Two-College Magery 	NA 	(-10%)	(-20%) 	(-30%) 	(-40%)
Three-College Magery 	NA 	NA 	(-10%) 	(-20%) 	(-30%)
Four-College Magery (maximum)	NA 	NA 	NA 	(-10%) 	(-20%)
==Comment==
As described Limited Colleges seems to conflict with Partially Limited Magery as full Magery 0 should detect all magic items (not just items with spells of the relevant colleges).
==One-College Magery==
===Classic===
In Classic it allowed the magery to apply to both Lend ST and Recover ST according to the FAQ, though the basic set only mentioned Recover (not Lend)
===Basic Set Version===
This breakdown demonstrates how to apply the revised rules from GURPS Thaumatology:
*Magery 0 (Limited (One) College Magery, -40%) [3] + Magery 1+ (Limited (One) College Magery, -40%) [6/level]
This breakdown is confirmed in the FAQ under 4.1.10 How does Aspected Magery work exactly?
===Fantasy===
GURPS Fantasy Pg 149 has an interesting sequence of mentions. In the first paragraph:
:A mage can have One-College Magery limited to the College of Enchanting (and the spell Recover Energy).
This thought is perhaps complete, but the second paragraph discusses "a ring enchanted with Deflect Missile"
Deflect Missile (M143) has Apportation as a prereq, and that is a spell which requires Magery 1, meaning that someone with Magery (Enchantment Only) could not fulfill the prereq to learn Apportation, and thus could not learn Deflect Missile to make that item...
2006 thread http://forums.sjgames.com/showthread.php?t=16565 highlighted this.
However: 2nd paragraph isn't necessarily assuming the mage in paragraph 1 made the deflection ring.
HOWEVER: see USELESS note below
==USELESS note==
Unusable Prerequisites aka useless prerequisites on T26 pertains to this. Example of dilemma:
:one has to know two “Seek” spells in order to learn Seeker – but in a strictly normal or lower mana world, someone who has Magery 1 with One College Only (Knowledge) can’t cast those spells,
Standard assumption is you can still learn the skill despite lacking magery needed to use. A potential problem for those questionioning "How can a wizard be said to know or understand a spell that he has never cast?" *alternate option is to lock them out due to being unable to complete a spell chain
*or: to justify standard assumption by imagining they go to High Mana places to cast it
The idea you can't know/understand spells you've never cast also creates problems with the Ritual Magic system where technique penalties could reduce effective skill of a Path to as low as 3: still making it POSSIBLE to cast the spell, but making it unlikely a Ritual Mage would've taken the risk at doing so given the high likelihood of critical failure.
One interesting compromise might be to borrow from Wild Talent rules. Using B99's Retention enhancement, even after spending 1 character point to learn a skill, there is a taboo (those are worth 0) against improving it (either via spent CP or 200 hours study time) for 1 month, plus a -2 penalty. Only a crit success on WT's IQ roll prevents that.
*the -4 for missing prereqs is harsher than the -2 for missing prereqs that happens in
==Important Note Regarding Enchantment==
Magery (Enchantment only) is not the same as Magery (Limited College, Enchantment). Rer Partially Limited Magery rules the first limits how the spells are cast while the second limits the number of castable spells (Magery 1+ spells of the Enchantment College and spells not requiring magery).
The RAW produces a real mess if Magery 0 (Limited College, Enchantment) is used. While spells outhsie the Enchantment College not requiring magery could still be learned they couldn't be cast...which means they couldn't be enchanted into items.
==References==
*GURPS Thaumatology 25
*GURPS Thaumatology 42
Category:Limitations