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Old 02-29-2024, 03:26 PM   #1
Giovanni
 
Join Date: Feb 2016
Default Unstable Mana: magic system variant.

I love a lot random spell effect tables I found on the net. I wonder how to use them with GURPS. I have thought about this system...it's a bit an unfinished job but with some adjustments I think it could work well.

This variant use the spells from Magic.
I actually play 3rd edition so I have in mind the relation between Strenght and FP but with 4th edition it should work also.

How it works?
* Each morning a magic user convert some FP in 'mana dice': 2 FP generate a mana dice. Any number of dice can be generated this way: 4-6 mana dice are recommended.
* When a magic user attempts to cast/mantain a spell it rolls all mana dice he have in the pool:
- if a dice shows a result from 2 to 4 then 1 point of spell cost is covered.
- if a dice shows 1 it is exausted and forever eliminated from the pool.
- if a dice shows 6 something strange happens: you can use a table of random magical effects on the net. The more 6 are present in a roll the bigger the trouble.
* when the magic user sleeps all mana dices are lost.

That's all.
Of course smaller mana dice pool will be safer but they will deplete soon and they will also make difficult or impossible to cast or mantain spell with high cost.
Larger mana pool will be riskier to use but they will also allow very costly spells.

Last edited by Giovanni; 02-29-2024 at 03:30 PM.
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Old 02-29-2024, 03:46 PM   #2
Varyon
 
Join Date: Jun 2013
Default Re: Unstable Mana: magic system variant.

Let's see if I understand this correctly. Basically, the magic user has to decide upon waking up how much of a mana pool they want to have, up to a maximum of FP/2. Does producing this pool cost FP (requiring you to rest for 20 minutes per die generated, meaning magic users will wake up, then pretty much immediately have to sit and rest for a while), or is the amount of FP the character has simply serving as a limit?

Next, when casting, if you don't generate enough energy for the spell on this roll, does that mean the casting fails, or do you keep rolling your pool until you either have enough energy or you run out of dice (due to rolling 1's)? If the latter, does it take additional time for each roll, and if so, what relationship does this have with the spell's normal casting time?

Is the energy generated by your mana pool free, or do you still need to pay FP for each point of energy?

If using the energy-gathering option from above, do the random effects occur immediately, or upon actually casting the spell? They kinda sound like more extreme versions of RPM's quirks, so I could see them potentially building up over the course of multiple gathering attempts. If using that option and you abort the spell (or are incapacitated before you can finish it), what happens to it and any "quirks" it has accrued?

My immediate reaction is that I wouldn't want to use this system at all - not only because I tend to have poor dice luck (and thus would likely lose my pool rather quickly) but also because these appear to do the equivalent of a critical failure at least 17% of the time and typically a lot more (the average of your suggested range, 5, has around a 60% chance of rolling at least one 6).
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Last edited by Varyon; 02-29-2024 at 03:53 PM.
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Old 02-29-2024, 10:14 PM   #3
Giovanni
 
Join Date: Feb 2016
Default Re: Unstable Mana: magic system variant.

Quote:
Does producing this pool cost FP (requiring you to rest for 20 minutes per die generated, meaning magic users will wake up, then pretty much immediately have to sit and rest for a while), or is the amount of FP the character has simply serving as a limit?
It should cost FP. It should serve as a limit. But maybe it's not a good idea. Maybe, in the morning, each magic user sould choose between 4,5,6,7, or 8 dice mana pool.

Quote:
Next, when casting, if you don't generate enough energy for the spell on this roll
The spell fails and, in order to retry, you need another action.

Quote:
Is the energy generated by your mana pool free, or do you still need to pay FP for each point of energy?
It's free.

Quote:
Do the random effects occur immediately
Immediately.

Quote:
My immediate reaction is that I wouldn't want to use this system at all - not only because I tend to have poor dice luck (and thus would likely lose my pool rather quickly) but also because these appear to do the equivalent of a critical failure at least 17% of the time and typically a lot more (the average of your suggested range, 5, has around a 60% chance of rolling at least one 6
It's not intended to use the critical failure table. Random effect should be hilarious (think about wild sorcery in D&D 5) and maybe a bit annoying but not life threatening (unless you roll a lot of 6 of course).

Last edited by Giovanni; 02-29-2024 at 10:20 PM.
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Old 02-29-2024, 10:29 PM   #4
Fred Brackin
 
Join Date: Aug 2007
Default Re: Unstable Mana: magic system variant.

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Originally Posted by Giovanni View Post
It's not intended to use the critical failure table. Random effect should be hilarious (think about wild sorcery in D&D 5) and maybe a bit annoying but not life threatening (unless you roll a lot of 6 of course).
Or unless you're trying to use your magic for some life-saving purpose. Having a "Wand of Wonder" set on "Explosive Overload" go off when you're trying to save somebody's life might not be hilarious.

So maybe this is a campaign where no pone tries to do anything important. The PCs just wander around until somebody tries to cast a spell because they're bored.
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Old 03-01-2024, 04:45 AM   #5
mburr0003
 
Join Date: Jun 2022
Default Re: Unstable Mana: magic system variant.

Quote:
Originally Posted by Giovanni View Post
I have thought about this system...it's a bit an unfinished job but with some adjustments I think it could work well.
Interesting concept... I have some thoughts.

I do think instead of limiting it on FP, you should let them fill the pool each with a ritual (and at any time). Say they can spend [TIME UNIT] drawing in mana, this requires a Meditation or Thaumatology or Ritual Magic skill roll. This way skill is somehow still required (I like Ritual Magic for this myself, maybe Meditation for an aesthetic, Thaumatology for a Hermetic, etc). Each [TIME UNIT] spent performing rituals, meditating, contemplating the function of the prime transposition of a gryphon's feather with a cow egg (Thaumatology) allows them to draw the skill roll's MoS in "Mana Dice" (or MoS+ Magery, gives Magery a boost so it still feels like a valuable Advantage to buy up past 0 1*) into their pool.

I'd say up to a limit of either the skill†, or maybe IQ+Magery (so Magery is still doing something here as well), or whatever. Or maybe no real limit†, the actual limit could be they always have to use a minimum of 1/5 of their dice pool, meaning that going all POWER OVERLOADING will likely have more serious consequences.

Also I'd swap around how the dice results work. 1s in GURPS should always be good, basically critical successes, this is how I'd do it:

Roll of 1 gives 1 Mana for the spell's casting and does not deplete the die.
Rolls of 2-5 give 1 Mana and deplete the die.
Roll of a 6 has that Man "going wild", the die gives Mana and is used in rolling on the Wild Spell Charts.

Also, since some spells have massive cost, I'd allow the PC to keep performing the ritual to cast (so if it's a 1 second Casting Time spell the ritual takes 1 second, if it's 10 minutes Casting Time the ritual takes 10 minutes), so basically they roll a number of their Mana Dice every [how ever long the spell takes to cast] channeling their Mana Pool until they have enough to cast the spell, excess Mana is lost to the casting once they've gathered enough. They can stop casting at any time, the Mana channeled is lost, harmlessly if they roll no 6s, or with weird effects if they did. They can also channel FP into the spell with each "ritual pass" speeding things up, but making themselves tired in the process (or don't use "passes", they roll all the dice they want to risk in the spell at once and either generate enough Mana or don't - personally I like letting keep performing the ritual, so even an 'easy quick' spell could end up taking two or three times as long if they don't dedicate enough dice on the first roll or two).

This way if they only need 1 to 3 Mana for a spell, they don't have to roll 10+ dice with as great a risk to losing dice or going wild. They could just roll even 1 die, knowing they can bolster it with FP even if it goes wild.

This also gives them a pool that depletes rapidly as it's used (just like FP does in the vanilla system), but they can refill it after major spellcasting if they have time to perform the 'ritual of gathering mana'.


Alternately, have no "mana pool" do a straight up "gathering energy" as part of a spell's casting. In this setup when they cast a spell they roll the spell's Skill, the ritual length is the Casting Time (yes so spell skill does double duty here - but this means at low skill level spells take much longer so that's something to consider, it makes less skilled mages vastly 'weaker' than high skilled mages), at the end of each Casting Time they roll spell skill and 'gather' the MoS of the roll in Mana Dice. Those dice are immediately rolled to generate mana for the spell. All Mana Dice rolled generate 1 (or more) mana, 1 can be held aside in a "mana pool" and not used right now or they may be spent to generate 1 mana and be immediately rerolled for the possibility of extra mana right now, 2-5 are expended immediately, 6s are expended immediately but also go "wild" as the spell is cast. Once enough Mana is generated, the spell is cast (no further rolls are needed) and any 6s rolled are used on the Wild Spell Chart.

This way the spell's skill has meaning aside from just Casting Time and Mana Cost Reductions, but higher skill will feel like it's double dipping and a bit "cheaty". Which might be a good thing, it will make truly skilled wizards feel more potent.

If the mage decides to hold 1s in a pool, then for every length of time (say 10 minutes feels good), they have to roll a HT based Thaumatology roll or suffer mana burn. They either take their mana pool in dice of damage (with weird effects, like it could be frost, fire, acid damage, maybe it's a "immediately influenza" that just deals HP damage and their 'sick' until it's fully healed, or whatever) or it releases as random spell with Wild Spell results. Basically if their HT based Thaum roll fails, they lose control of their "held" mana, meaning it's best to use the mana pool they hold over on a few spells in the next few castings instead of trying to build up a big spell pool from a bunch of spell work all day for a mega spell later.



Whatever you do, I do think swapping your 1s and 6s are important. That keeps with the GURPS theme of "rolling low is good (except on damage and the NPC Reaction Chart)".



* Right, 3rd ed. GURPS 4e has Magery 0, then Magery 1+. Magery 0 is the "intro" Magery level that allows spell casting and sensing magical items and mana levels, but gives no bonuses to spell casting and costs 5 points. Magery 1+ is 10 points and may be bought to whatever level the GM limits for the game.

† Whatever skill you prefer, Thaumatology is a good one for this, or IQ+Magery, or the average of thei spell skills, or whatever you think is best. Or if you do no limit, then always require a minimum number of the Dice Pool be used, thus limiting how crazy high the Player will want eh pool to go (though note, most "Wild MAge" Players will embrace the chaos and like the problem players they are will be seeking to POWER OVERWHELMING every spell they can - just my experience with the Wild Magic system and the Players who loved it in AD&D 2e).
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Old 03-01-2024, 06:11 AM   #6
Giovanni
 
Join Date: Feb 2016
Default Re: Unstable Mana: magic system variant.

Quote:
Alternately, have no "mana pool" do a straight up "gathering energy" as part of a spell's casting. In this setup when they cast a spell they roll the spell's Skill, the ritual length is the Casting Time (yes so spell skill does double duty here - but this means at low skill level spells take much longer so that's something to consider, it makes less skilled mages vastly 'weaker' than high skilled mages), at the end of each Casting Time they roll spell skill and 'gather' the MoS of the roll in Mana Dice. Those dice are immediately rolled to generate mana for the spell. All Mana Dice rolled generate 1 (or more) mana, 1 can be held aside in a "mana pool" and not used right now or they may be spent to generate 1 mana and be immediately rerolled for the possibility of extra mana right now, 2-5 are expended immediately, 6s are expended immediately but also go "wild" as the spell is cast. Once enough Mana is generated, the spell is cast (no further rolls are needed) and any 6s rolled are used on the Wild Spell Chart.
Sure: I prefer this variant.
It looks very good.
Maybe 1+MoS is the maximum mana dice you can gather.
So, for a low cost spell, if you want to go with a sure cast you can.
But very expensive spells will require both high skill and high risk.

EDIT:
1 on a mana dice could be
* 1 point of the spell cost covered and.....
* mana dice is rerolled.

Last edited by Giovanni; 03-01-2024 at 07:10 AM.
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Old 03-01-2024, 08:41 AM   #7
Fred Brackin
 
Join Date: Aug 2007
Default Re: Unstable Mana: magic system variant.

Quote:
Originally Posted by Giovanni View Post
So, for a low cost spell, if you want to go with a sure cast you can.
But very expensive spells will require both high skill and high risk.

E
Only in mburr's variant is there a "sure cast" as 6s will still deliver energy as well as sparking some bit of chaos. In your original version there was no such thing as both 1s and 6s gave no energy.

Even in the 2nd variant there is no "safe" cast unless you are trying for a Spell that costs 1 pt only and 1 pt of chaos is supposed to be annoying only. Multiple chaos dice will always be possible when multiple pts of energy are required.

If this was the only Magic system offered I might try for a non-magical group.
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Old 03-01-2024, 08:50 AM   #8
johndallman
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Join Date: Oct 2010
Location: Cambridge, UK
Default Re: Unstable Mana: magic system variant.

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Originally Posted by Fred Brackin View Post
If this was the only Magic system offered I might try for a non-magical group.
Same here. Under this system, magic cannot be relied on at all.
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Old 03-02-2024, 03:09 PM   #9
mburr0003
 
Join Date: Jun 2022
Default Re: Unstable Mana: magic system variant.

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Originally Posted by johndallman View Post
Same here. Under this system, magic cannot be relied on at all.
Depends on what the Wild Magic Charts look like. Crit fails already cause magical mishaps in vanilla GURPS and an awful lot of GMs like to do "extra stuff" on crit successes (which may or may not be to the Player's liking or their own perceived advantage - especially if the GM like to use the group's Weirdness Magnets against them during crit spell castings).
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Old 03-02-2024, 04:03 PM   #10
johndallman
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Location: Cambridge, UK
Default Re: Unstable Mana: magic system variant.

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Originally Posted by mburr0003 View Post
Depends on what the Wild Magic Charts look like. . .
That's not the issue; the problem is that you don't now how much energy you can use. Using GURPS Magic spells sensibly requires knowing how much energy you have available.
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