Creating A Permanent Spell Effect (5e Variant Rule)
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Creating a Permanent Spell Effect
In the PHB, a spell helpfully mentions that if you cast a Nystul’s Magic Aura (level 2) on the same item every day for 30 days, it becomes permanent. This is not the only spell that states repeat casting will create a permanent effect, such as teleportation circle (level 5) which the DMG stipulates casting the spell every day for a faerun year (which is exactly 360 days) will cause it to become permanent.
Although not explicitly presented as a universal rule, the concept is useful, as it gives a justifiable way to create persistent magical environmental effects without having to be incredibly high level, and without having to make permanent versions of normal spells. In other words, it's a nice mechanical shortcut if you use it.
From these two existing spells we can deduce a few things.
Spells that can be made permanent. Nystul’s Magic Aura, Private Sanctum, teleportation circle, Wall of Stone, True polymorph, the list goes on. There does seem to be a trend amongst the spells that can be made permanent. Some can be made permanent via repeat casting, others by maintaining concentration for the entire duration, and others via up casting to higher levels.
In truth we should not be thinking of making a hard rule and using spread sheets to determine the requirements, however we all know that is exactly what you came here for. So allow me to be brash and make a few blanket statements and a few assumptions in order to create something useful.
1st off it is clear to see that spell level does not actually play any major role in the number of times needed to cast these spells. While the developers may have had it in mind, it was not what they based their creations on.
2nd it seems that the scale of the spell has more to do with its difficulty than anything else. Teleportation circles scale can be imagined and private sanctum effects an area hundreds of feet wide. However magic aura effects only a single object or creature.
3rd in relation to normal duration and up casting. If all you need is a flat way to tell your players they need to be more powerful, than right now I can tell you it is more than reasonable to say casting any spell lower than 5th level at 9th level can make it permanent.
Making something useful.
Inevitably it seems we have no choice but to look at downtime activities and downtime availability, but there is hope for a more expedient solution.
based on the spells I have read and my knowledge of the downtime table for character growth and training, I have come up with this simple method.
take the spells casting time and duration to assign a value.
|C * rounds||7|
|C * minute||6|
|C * 10 minutes||5|
|C * hour||4|
Now that we have something to work with, lets see how it looks in practice. casting time * duration, then * level = days needed to cast.
Magic aura. level 2. casting time 1 action. duration 24 hours.
14*1 * 2 = 28 days
teleportation circle. level 5. casting time 1 minute. duration 1 round.
10*7 * 5 = 350
I had tried to find a clean way to make it match more pinpoint to these two spells but ultimately doing so will require arbitrarily making specific modifiers higher or lower than the others around them and breaking any sense of scaling. You can feel free to alter the numbers as you see fit for your campaign as this is purely a guideline only meant to help you make your own choices.
Now that we have that out of the way. Lets go even further down this rabbit hole.
Honestly I find it unreasonable how 5e did not include a permanency spell or any specific rule set to guide our weary souls.
Ultimately we are the masters of our own worlds and thus we can do whatever we see fit to make the game as enjoyable as possible for ourselves and our players. Thus it is dead simple for us to bring back from the abyss that which the developers were either too lazy or too lacking to implement.
In the old days the permanency spell was a level 5 spell that was placed in that level due to its harsh requirements. Such a powerful spell was only just above mid level because it was nearly impossible to make any use of it due to its harsh gold costs and due to the makers placing harsh restrictions on what it could or couldn't make permanent.
But we are not the block headed fools of the past and we have learned that harsh arbitrary restrictions 9 times out of 10 does not make for a fun and enjoyable experience.
So with that in mind I suggest this revamped version of the permanency spell.
casttime= see text
range= a level 4 or lower spell
comp= V, S, M (a jewel worth at least 250gp per level of spell empowered (minimum 100gp), which the spell consumes)
As you cast the spell, you must have an off hand free. Holding the jewel in your main hand you may use your off hand you cast a single spell. Doing so will cause the jewel to crumble to ash as it empowers your spell to become permanent until dispelled. This spell does not work on any spell with a duration of "instantaneous"
The casting time of your spell becomes 1 hour if it was not already, or 1 day if it is longer.
At Higher Levels: When you cast this spell using a spell slot of 5th level or higher, the effect of this spell extends to spells of the same level.
Ritual variant rules:
Rituals are a special and long forgotten mechanic in D&D which I was sad to see go. The basic breakdown of what they are is essentially a complex series of actions and material requirements which can allow anyone, caster or not, to create wondrous and miraculous effects.
Rituals are formatted very similarly to spells, however their costs are far greater and contain hidden dangers. The primary caster does not need to be of any particular level, nor do they need to be a spellcaster. They do however require to be proficient in either Arcana or Religion.
casttime= 1 day
range= see text
comp= 1 primary caster proficient in Arcana or Religion (a source of power or a material worth no less than 1,000 gp per level of spell effected
The primary caster must create a source or location of power in which to draw upon to aid them in casting. This can range from (but not limited to), a 10,000 year old tree, the location where a great creature (such as a dragon, celestial or fiend) died, the body of such a creature or the combined efforts of at least 5 secondary casters.
Once the primary caster has attained a sufficient source of power, they must perform the ritualistic tasks in accordance to their source. Such as a live sacrifice to appease fiendish powers or sacrificing of a precious object to garner favor from gods or the world.
The primary caster must succeed on a DC 25 Arcana or Religion skill check as well as a DC 20 Constitution saving throw in order to perform their tasks to the best of their abilities and to not succumb to the wild or ancient powers they draw upon.
The DC of these skill checks and saving throws are reduced by 2 for every secondary caster which succeeds on their own Arcana or Religion skill checks. to a minimum of 15.
If the primary caster has at least 5 secondary casters, they have advantage on their Constitution saving throw.
If the primary caster has at least 10 secondary casters, they also have advantage on their Arcana or Religion skill check.
Each secondary caster must succeed on a DC 15 Constitution saving throw or be implicated in the potential backlash of a failure.
The primary caster has succeeded in extending the effect of a spell cast by either themselves, one of their secondary casters or that of a third party. The spell must be cast within no less than 10 ft. of the rituals centre. The spells effect shall be empowered to become permanent. This also extends to other effects, such as those from potions or magical objects that act as if casting a spell.
If the primary caster fails in the performance of their ritual a terrible backlash of magical power will occur.
The primary caster will take 4d10+10 Force damage and 1d4+1 levels of exhaustion. If they succeeded on their Constitution saving throw, they will take half as much damage and only 1 level of exhaustion. The secondary casters will take 2d10+5 Force damage and 1d2+1 levels of exhaustion. If they succeeded on their Constitution saving throws, they will take half as much damage and only 1 level of exhaustion.
Regardless of success, the ritual can only be attempted once per day by any of the casters involved. (meaning all casters must wait a day)