Spell Rarities

The level of a spell dictates its power, but not always its difficulty or prevalence. Some spells are known only to a scarce few mages who need them for their work, or even only those who invented them, while other spells are all but erased from history, with only minor references and snippets scribbled in the margins of the most ancient tomes. Some spells that could change the world as it is known are so difficult to master that only the most skilled mages ever bother to try, while some are simple displays of pure force that any mage of sufficient power may wield with ease.

This optional system serves to contextualize spellcasting in your world, generate interesting connections between players and their spells, and simultaneously provide an internally consistent method for limiting the players' magical abilities to manageable levels for the DM.

There are four rarities used in this system, and they are detailed below:

• Common: Almost every trained spellcaster, and even some untrained ones who have the ability to cast this spell use it often or know of it and have seen it used. Common spells are almost always easy to master for spellcasters powerful enough to wield them.
• Uncommon: Some spellcasters know of and use this spell, either due to its difficulty, its obscurity, or its niche applications. Most spellcasters will have at least some vague knowledge of this spell.
• Rare: Very few spellcaster know of or use this spell. This may be the personal spell of some powerful mage who created it, or it may have been forbidden long ago and only exists in the minds of a scarce few old wizards.
• Legendary: No living person in the known world still uses this spell, but there is some remaining record of it, whether in the far memory of some considerably ancient warlock (or their patron), the pages of a legendary lost tome, or in the text of a crumbling old scroll, which can withstand but one last casting before being lost to time.

Applying Rarity to Specific Classes

This system as written applies mostly to wizards, and seems less applicable to other classes. In this section I will provide thoughts and examples on how to apply the ideas behind spell rarity to other classes.

Cleric

Clerics do not learn spells, they are given their abilities through their devotion to their deity, faith, or other target of worship. Mechanically, clerics simply "know" all of their possible spells and just progress in the amount of power they have to cast more of them. This omniscient knowledge of course clashes with the idea of rarities in this system, but it can still be leveraged to function normally with a few considerations into how spells are distributed. There are three main ways to deal with clerics in this system:

1. Deities treat uncommon spells similarly to domain spells, only allowing certain clerics access to those powers based on their needs, and treat rare and legendary spells as special, direct divine gifts, heavily limited in their distribution. This provides a reasonable hierarchy of clerics with increasing access to certain powers, ending in only the highest and holiest being able to perform true miracles never seen by mortals.

2. Clerics know about all their spells, but may not necessarily be given the power to cast certain ones due to other factors, such as divine politics (i.e. gods of life not stepping on the toes of gods of death with spells like resurrection). This could allow for situations where a cleric has knowledge of a powerful spell, maybe even one that could resolve a problem very important to them, and they know their god holds it just out of their reach, creating a meaningful sense of doubt in one's own faith.

3. Simply create a different rarity distribution for clerics where everything is common. This of course may have unwanted connotations in terms of worldbuilding, such as widespread resurrections, longer lifespans, overpopulation, and an eventual obsolescence of death. this can all be hand-waved away of course, but this system is singularly intended to confront the consequences of widespread spellcasting head-on, so the omission of large details like this is not ideal.

Clerics cannot simply trade spells between each other with training and education, but they can petition their gods for special spells in times of need, and most likely keep them afterwards.

Druid

Druids, similarly to clerics, simply prepare their spells from a list of which they always know, and don't necessarily "learn" spells. The difference is their source of power for these abilities: their devotion to nature and its many aspects. This can sometimes appear very similar to a cleric, such as a druid that worships an aspect of the natural world (such as the cycle of life and death) as if it were a deity. Other times, druids may gain their power from their own understanding and acceptance of natural concepts, such as the cycle of water and how it affects different creatures.

When applying this system to druids, it can be flavored similarly to the way the Circle of the Land's circle spells work, in that only druids who deal in certain aspects of druidic arts gain the appreciation for the natural aspect needed to cast certain spells. For example, a spell like ice knife would be relegated mainly to druids hailing from icy tundras. For rare and legendary spells, more mysticism could be involved in their existence. For example, faeries could inject a particularly powerful spell, such as geas, into the minds of certain unstable druids in order to cause a bit of chaos for their enjoyment.

Druids can teach other druids their spells, but it is a significantly more difficult task if the druid is not able to experience the nature they seek to learn about first hand. Without spending time learning about the spells in the environment to which their aspects are linked, I would surmise that a druid can only reasonably learn spells of 2nd level or lower. This may of course differ in your view, but it is simply an example.

Paladin

Paladins function very similarly to clerics in terms of their spellcasting, and can use the spell rarity system in similar ways. Paladins derive their power from their oath, their conviction, and their belief in their deity or power. The spells they learn can be seen as gifts from that power, or simply as techniques that can be taught through training. If the case is the former, then the techniques for adapting clerics to spell rarity will work identically for paladins. If it is the latter, then uncommon spells can simply come down to a difference in training depending on where they learned their craft. For spells of rare or legendary, a divine gift suits their concepts more favorably, but they could simply be specially developed techniques specialized to one order of paladins, or even to a singular knight.

Obviously whether or not paladins can teach others their spells depends on whether they are divine gifts or techniques. However, like clerics, paladins can petition their deities for more power in times of need, and as such can sometimes be made to use special spells if the situation is dire enough.

Ranger

The magic available to rangers falls somewhere between the domains of a druid and a bard: The ranger's attunement to nature fuels their spells, and they can only know a scarce few at any time. Of course there is not much written on how a ranger learns their spells, but for this section I will assume that they learn them similarly to druids: through communal with aspects of nature.

Sorcerer

Warlock

Wizard