Sorcerers, elementalists, and warlocks each use magic points to determine exactly how many spells they may cast each day, with each spell costing its level in magic points to cast. Mystics, however, live with the uncertainty of psychic fatigue, where each spell they cast could be their last of the day. Using sorcerers as a baseline magic-point-using profession, this essay compares psychic fatigue to magic points as a measure of daily spellcasting.
Because mystic spells only run to ninth level, this essay only compares mystics and sorcerers from ranks one to nine.
Psychic Fatigue
Firstly, a quick recap on psychic fatigue. After each spell a mystic casts, a d20 is rolled to determine whether the spellcasting effort exhausts their reserve of magical energy. To avoid psychic fatigue, the roll mus tbe equal to or less than 13, plus their rank, minus the spell's level.
The probability of a first-level spell fatiguing a first-rank mystic is 7-in-20 (i.e., 14+ on a d20), or 35%, reducing by 5% per rank until it reaches 5% at seventh rank (a roll of 20 is always a failure).
Because psychic fatigue is only tested after casting a spell, the mystic always has 100% chance of casting at least one spell per day (of any level the mystic is able to cast).
First-Level Spells
First-level spells are the easiest for both mystics and sorcerers to cast and is a good starting comparison for the daily number of spells each of those magician professions may cast per day as they increase in rank.
| Magician's Rank | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | |
| Sorcerer's MP Total | 4 | 8 | 12 | 15 | 19 | 23 | 25 | 28 | 31 |
| Chance of Psychic Fatigue per First-Level Spell | 35% | 30% | 25% | 20% | 15% | 10% | 5% | 5% | 5% |
| Chance for Mystic to Cast as Many First-Level Spells as Sorcerer | 27% | 8% | 4% | 4% | 5% | 10% | 29% | 25% | 21% |
| Probable Number of First-Level Spells Per Day | 2 | 2 | 3 | 4 | 5 | 7 | 14 | 14 | 14 |
At their best, mystics are likely to cast approximately half the number of first-level spells as a sorcerer of the same rank and, at their worst, only about a quarter.
Maximum-Level Spells
Mystics are clearly not 'volume' spellcasters, but how do they compare against socerers when casting their highest-level spells — for example, a third-rank magician casting a third-level spell?
If a mystic's rank and the spell's level are the same, then the chance of psychic fatigue is 35%, as the bonus to going up in level is offset in equal amounts by the penalty for the level of the spell.
| Magician's Rank | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | |
| Maximum Spells of Highest-Level a Sorcerer May Cast | 4 | 4 | 4 | 3 | 3 | 3 | 3 | 3 | 3 |
| Chance for Mystic to Cast as Many Highest-Level Spells as Sorcerer | 27% | 27% | 27% | 42% | 42% | 42% | 42% | 42% | 42% |
| Probable Number of Highest-Level Spells Per Day | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
At no point does the mystic achieve parity with sorcerer in terms of spells cast per day, casting between half and two-thirds of their maximum-level spells as sorcerers.
Cunning Folk
Within the pages of Cadaver Draconis is a mystic path for the Cunning Folk, one of whose abilities is to forge a totem that grants them a +1 bonus to their psychic fatigue threshold for all spells beyond first level. This comes at a cost to the mystic's other abilities (including armour proficiency, Spell Mastery, magical armour and weapon crafting, and up to eight of their spells), but what difference does this make to the number of spells they can cast per day?
First-level spells are unaffected, of course, but it does change the probabilities of the maximum number of highest-level spells.
| Magician Rank | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | ||
| Maximum Spells of Highest-Level a Sorcerer can Cast | 4 | 4 | 4 | 3 | 3 | 3 | 3 | 3 | 3 | |
| Chance of a Cunning One Casting as Many Highest-Level Spells | 34% | 34% | 34% | 49% | 49% | 49% | 49% | 49% | 49% | |
And whilst 49% is definitely higher than 42%, it is not 50% or higher, so the likely number of highest-level spells that a Cunning One will be able to cast per day remains the same as for a normal mystic (i.e., 2).
Conclusion
So, there you have it, no surprise that mystics are nowhere near the spellcasting machines that sorcerers are. The two scenarios — casting their easiest spells and their hardest spells — is designed to show the relative boundaries of daily spellcasting for sorcerers and mystics. Actual adventuring spellcasting is likely to require a mix of spell-levels so actual daily spellcasting will likely fall somewhere in the middle. With mystics likely casting anything around a quarter to two-thirds the number of spells as a sorcerer during an adventure, their spellcasting capacity is more comparable to that of a warlock.
This analysis could be extended to include magic points a sorcerer may invest in scrolls and wands, just as the mystic's Spell Mastery could be considered one of their cast spells for the day (just with a long duration), but such variations are very much personal to the individual sorcerer and subject to how 'spellcasting' is to be defined — something that is beyond the scope of this short essay to consider. This is not, after all, an essay about game balance, just a simple comparison of daily spellcasting capacity.