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Old 08-28-2019, 10:45 PM   #1
Plane
 
Join Date: Aug 2018
Default spell prereqs, just for learning or also for casting?

B234/235 talks about prereqs using the verb "learn".

Once you have actually learned a spell, is there any need to continue possessing the prerequisite spell or level of magery?

B294 has rules for how skills might degrade, for example, so if you had 1 point in purify air, learned create air, then lost purify air due to lack of practice (forgot to use it during the 6 months and failed your IQ check) would you still be able to use create air just fine?

There are also spells which can steal magery levels, dropping them permanently. If you need magery 1 to learn fireball, learn it and then your magery drops to 0, could you still keep casting it even though you lack the magery to learn it anew?
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Old 08-28-2019, 11:20 PM   #2
Refplace
 
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Default Re: spell prereqs, just for learning or also for casting?

I think its gong to have to be an interpreted house ruling.
I would say generally learn not cast as the prerequisite helped you learn but once you spent the point you know it. However things like levels of Magery I would consider needed to cast.
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Old 08-29-2019, 12:26 AM   #3
Plane
 
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Default Re: spell prereqs, just for learning or also for casting?

I just took a closer look at M130 "Drain Magery"
cannot cast those that require a higher degree of Magery than his new one.
Presumably that would also apply to the spellcaster if a critical failure resulted in their magery dropping below requirements too, or someone who was able to get Magery 1 for only short periods of time (say with "Maximum Duration" magery?) where they wouldn't be able to cast when the magery level requirement was off.
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Old 08-29-2019, 12:34 AM   #4
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Default Re: spell prereqs, just for learning or also for casting?

The requirement is "You must know a spell in order to cast it" M7. That's it. Even that can be bypassed by Magic items or Wild Talent.

Prerequisites are "requirements you must meet in order to learn the spell" M6. There's no mention of casting. This can be bypassed by Wild Talent with Retention, because the specific rule for Retention trumps the general rule above.

Under Wild Talent enhancements Retention M99 "if you lack any of the skill’s prerequisites, your skill is at -4 until you acquire them, and you cannot improve the skill in the interim."
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Old 08-29-2019, 01:00 AM   #5
Plane
 
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Default Re: spell prereqs, just for learning or also for casting?

Quote:
Originally Posted by Balor Patch View Post
The requirement is "You must know a spell in order to cast it" M7. That's it. Even that can be bypassed by Magic items or Wild Talent.
So do you think the "Drain Magery" guideline of requiring magery to cast only applies when it is drained via the spell but not when it is lacking due to some other reason?

Quote:
Originally Posted by Balor Patch View Post
Prerequisites are "requirements you must meet in order to learn the spell" M6. There's no mention of casting.
Except under the Meta College "Drain Magery", M130.

Quote:
Originally Posted by Balor Patch View Post
This can be bypassed by Wild Talent with Retention, because the specific rule for Retention trumps the general rule above.

Under Wild Talent enhancements Retention M99 "if you lack any of the skill’s prerequisites, your skill is at -4 until you acquire them, and you cannot improve the skill in the interim."
Do you think this would also be a good guideline to use when someone lacks them after having them before, like with forgetting them due to lack of practise?

Skill/spell prereqs aside, casting at -4 per missing level of magery prereq seems like an interesting compromise between no penalty and inability to cast.

Of relation to this: M158 "Steal Skill":
If the victim had other skills based on the stolen one, he retains them fully, but the loss of a prerequisite causes a -2 penalty to skill use.
"Based on" sounds like when you buy it up from a default from the other skill, which probably wouldn't apply if you lost the skill altogether, so I don't know if this would apply to lack-of-practise forgetfulness.
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Old 08-29-2019, 02:53 AM   #6
Anthony
 
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Default Re: spell prereqs, just for learning or also for casting?

The Forgetfulness spell (M135) can cause someone to forget a prerequisite, and if it does, the spells that it's a prerequisite for can still be cast, but at -2 skill (this is consistent with, but clearer than, the text for steal skill). It seems consistent to do the same thing for other means of losing a spell.
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Old 08-29-2019, 03:15 AM   #7
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Default Re: spell prereqs, just for learning or also for casting?

Quote:
Originally Posted by Plane View Post
So do you think the "Drain Magery" guideline of requiring magery to cast only applies when it is drained via the spell but not when it is lacking due to some other reason?
On Thaumatology page 20 you will find rules for (partially) Limited Magery, including this example:
Quote:
One wizard buys Magery 1 for 15 points and a further two levels of Magery with the Solitary limitation for another 12 points. He can learn and cast Lightning, Major Healing, and Recover Energy. He can also learn Stone to Flesh and Lockmaster, but to use them, he must tell his friends to back away a few yards
In other words, if for any reason you don't have enough Magery to satisfy the prerequisites of a spell, you can not cast that spell until you do.
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Old 08-29-2019, 02:35 PM   #8
Plane
 
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Default Re: spell prereqs, just for learning or also for casting?

So based on the Steal Steal / Forgetfulness precedents, you're -2 to skill for each missing prereq skill/spell and can presumably still improve it (rather than the -4 for Wild Talent and being unable to improve it?)

and based on the Drain Magery / Limited Magery precedents, Magery prereqs are both a "learn" and also an unwritten "cast" requirement too.

The only thing left to wonder about I guess is with cases like where "Empathy" is a possible prereq alternative to magery, such as with Lend Energy.

This does settle something of a dilemma for casters who want Recover Energy, but don't want magery which applies to the Healing College to select its prereq Lend Energy:

You could perhaps write up in your background that they had learned Lend Energy and Magery (One Spell Only: Lend Energy) in the past, but had since forgotten them from lack of practice?

Then, those mages lacking Lend Energy could simply be -2 to Recover Energy due to missing prereq, but could still use it?

I say "use" rather than "cast" since it seems to operate like a passive skill. I'd like to see a version of it that operates like other spells, like maybe give it a duration of 10 minutes? It's not like failing would be a big deal since you could just brute-force a success until you got into your "recovery trance" or whatever it's meant to be (seems to recover rest).

The need for words/gestures like other spell would fit with meditative stuff.
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Old 08-29-2019, 04:30 PM   #9
Anaraxes
 
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Default Re: spell prereqs, just for learning or also for casting?

Prereqs help model a setting where magic is a coherent body of related knowledge with underlying principles (as opposed to, say, one-off spells each with its own unique formula that can or must be followed mechanically).

It's hard to imagine a pyromancer that can throw fireballs, create walls and fire, etc yet can't light a candle. Conveniently forgetting that prereq to his college just to save on points ought to be worth a penalty -- he no longer really possesses the knowledge he's supposed to, as reflected by the lowering of his skill points in the college.
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Old 08-30-2019, 05:38 PM   #10
Plane
 
Join Date: Aug 2018
Default Re: spell prereqs, just for learning or also for casting?

Quote:
Originally Posted by Anaraxes View Post
Conveniently forgetting that prereq to his college just to save on points ought to be worth a penalty -- he no longer really possesses the knowledge he's supposed to, as reflected by the lowering of his skill points in the college.
A cumulative -2 would cover that for missing the immediate prereqs, but in the case of something like Explosive Fireball, with only Fireball as a prereq you could cast it at -2 even if missing the 2 spell prereqs to Fireball itself (create, shape) which would make you cast fireball at -4...

Not to mention the weirdness of: since Magery 1 is a prereq for Fireball but not explosive Fireball, dropping down to Magery 0 would mean you could cast Explosive Fireball but not fireball?

To avoid that weirdness, I think maybe not just immediate (listed) prereqs should matter, but also prereqs for those prereqs? Ie you'd need magery 1 to cast explosive fireball as well?

On the other hand... we do sometimes see spells who have a prereq spell requring magery also listing magery as a prereq, as with Lend Energy > Recover energy, though that's muddied by Magery 1 being an optional prereq for LE since Empathy can sub.
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