School of Shadow Calculus
The unspoken is a variable, never a confession owed.
Lore Overview
Shadow Calculus studies absence: the pause before an attack, a concealed motive, the missing term in a magical proof. Choose this school to become a patient analyst whose predictions expose tactical openings without granting ownership of another person’s truth.
Shadow Calculus specializes in Shadowlust: dream, altered perception, illusion, private identity, and hidden longing. Its predictions study what can be observed and inferred, while its magic preserves the distinction between an uncovered clue and a confession freely given.
Predictive defense and focused control. You identify a subject and calculate its next threat. Rising Arousal makes an opening easier to exploit; Libido sharpens defensive predictions; Climax changes the subject of your inquiry.
Subclass Features
| Sigilwright Level | Feature |
|---|---|
| 2nd | Shadowlust Research |
| 2nd | Unseen Variable |
| 2nd | Calculated Temptation |
| 2nd | Ritual and Social Identity |
| 6th | Exposed Term |
| 10th | Closed Manuscript |
| 14th | Proof of Omission |
Shadowlust Research
2nd-Level Subclass Feature
You specialize in Shadowlust. The following spells are additional Sigilwright spell-list options for you through this subclass: Whisperglass Trace, Shade Decoy, Mirror of the Unsaid, Veilbound Echo. This is an explicit access exception for these named spells only, including those whose printed Available Classes omit Sigilwright.
These spells are not automatically known, added to your spellbook, or always prepared. Learn them using your normal two spells per Sigilwright level or copy a discovered formula using the normal time and gold costs. You must have slots of the spell’s level before learning it, then prepare and cast it normally using Intelligence. This feature grants no free castings, additional spells learned, or additional prepared spells. Your ordinary access to other eligible Grimoire and 2014 Wizard spells is unchanged.
A qualifying Shadowlust spell is a spell you cast as a Sigilwright spell with that discipline explicitly printed in its rules. A blended spell qualifies if it includes Shadowlust, but counts as only one casting. Theme, traditional school, patron, and visual description alone do not assign the discipline. This tradition does not restrict you to its favored discipline.
Unseen Variable
2nd-Level Subclass Feature
You gain proficiency in Investigation, or Insight if already proficient in Investigation. As a Bonus Action, visibly mark one creature you can see within 60 feet with a shadow sigil for 1 minute. This is a magical effect, not a condition. It ends if you are incapacitated or mark another creature. You can mark a creature PB times per Long Rest. Once per round, when the marked creature makes an attack roll against you or a willing ally you can see within 30 feet, you may use your Reaction to subtract 1d4 from the attack roll. Decide after the roll but before the hit is determined. You must see the attacker.
Calculated Temptation
2nd-Level Subclass Feature
This technique modifies Unseen Variable. Use the expression for your table’s chosen play mode; it has no additional Classic Play effect.
Veiled Play. Once on your turn after a levelled Sigilwright spell, gain 1 Arousal, or use that casting’s Summation gain, to add 1 to your next Unseen Variable reduction die before your next turn. This cannot stack.
Unveiled Play. When using Unseen Variable, spend 1 Libido to roll d6 instead of d4. If the mark has at least 3 Arousal, also add 1 to that die. No Arousal is gained or removed by this expenditure.
Ritual and Social Identity
2nd-Level Subclass Feature
During 10 minutes of voluntary research, record one unresolved question about a document, magical scene, or statement you personally encountered. Once per Long Rest, gain Advantage on one Investigation check during the next hour to find an observable inconsistency in that evidence. Success yields a clue the evidence supports, not a private thought or automatic confession. A willing collaborator may provide anonymized observations; neither personal disclosure nor intimacy is required. Practitioners protect archives and investigate curses, omissions, and fraudulent ritual claims.
Veiled Play. When the research ends, you may gain 1 Arousal to gain advantage on your next EROSave before your next long rest, once per long rest.
Unveiled Play. When the research ends, you may spend 1 Libido to reduce your Arousal by 1 and give one willing collaborator advantage on its next EROSave within 1 hour. This grants no mark or Perfection.
Exposed Term
6th-Level Subclass Feature
Once on each of your turns when your marked creature fails a saving throw against a Sigilwright spell you cast, reduce its Speed by 10 feet (minimum 0) until the start of your next turn. This reduction does not stack with itself.
Veiled Play. If Summation gave you Arousal this turn, you may require the marked creature that failed the spell save to make an EROSave; failure grants 1 Arousal and success has no additional effect.
Unveiled Play. If the marked creature has at least 3 Arousal after failing its spell save, its Speed reduction is 20 feet instead of 10. You may spend 1 Libido to reduce your own Arousal by 1 when applying that greater reduction.
Shadow Correlation. Once per mark, immediately after you finish casting a Sigilwright spell of 1st level or higher bearing the Shadowlust discipline, you may transfer the existing mark to a creature you can see within 60 feet that was targeted by that casting. You may instead retain the existing target. If you transfer it, keep its remaining duration and expended once-per-mark benefits. This requires no action, grants no knowledge of concealed creatures, and cannot turn an illusory duplicate or an object into a valid creature target.
Closed Manuscript
10th-Level Subclass Feature
You gain Advantage on saving throws against effects that read your thoughts or determine whether you are lying. This does not impede ordinary Insight checks. Once per Long Rest in Classic Play, when your marked creature drops to 0 hit points, you may move the existing mark to a creature you can see within 60 feet without an action, retaining its remaining duration.
Veiled Play. After your Climax grants Perfection, spend this feature’s once-per-Long-Rest use to move the mark. Your next reduction die after the resulting Perfected spell gains +2, replacing any +1 bonus.
Unveiled Play. After the Perfected spell resolves, spend 1 Libido and the once-per-Long-Rest use to create a fresh mark without spending a Bonus Action or ordinary mark use. Its first reduction die is rolled twice; use either result. This grants no information about private thoughts.
Perfected Inference. When you finish casting a Perfected Shadowlust spell while your mark is active, the marked creature cannot make Opportunity Attacks against you until the end of the current turn, provided you can see it within 60 feet. This grants no movement and does not suppress other Reactions. It applies once for that Perfected spell, whether or not you expend Closed Manuscript’s separate once-per-Long-Rest benefit.
Proof of Omission
14th-Level Subclass Feature
Your Unseen Variable die becomes 1d6; spending Libido through Calculated Temptation increases it to 1d8 instead. Once per Long Rest, after your marked creature misses because of Unseen Variable, require a Wisdom saving throw against your spell save DC. Failure prevents Reactions until the start of its next turn; success has no effect.
Veiled Play. If Greater Summation or Summation Mastery prevented your Arousal gain since your previous turn began, the feature’s once-per-Long-Rest restriction uses an EROSave instead of Wisdom. It adds no Arousal.
Unveiled Play. When the baseline Wisdom save fails, spend 1 Libido to give the marked creature 1 Arousal. At this level, Unseen Variable’s ordinary die is d6 and its Libido-funded die is d8; this does not grant an extra Reaction.
Additional Information
Combat Identity
Predictive controller who accounts for hidden intentions and incomplete knowledge.
Desire Identity
Held pressure and restrained revelation inform a proof whose missing terms matter.
Class Integration
You gain these features at Sigilwright levels 2nd, 6th, 10th, 14th. This subclass works through Summation and Perfection. Use the costs, triggers, limits, and recovery stated in the individual features and parent class.
Using This Tradition.
The live Mechanics of Desire and Sigilwright pages govern these features, subject to the creator’s numerical Veiled Play clarification here. PB means Proficiency Bonus. Subclass EROSave DC = 8 + PB + Intelligence modifier. An EROSave uses the target’s chosen Constitution or Wisdom saving throw, including proficiency only when proficient in that saving throw.
Ritual and Social Use
Respect what a participant chooses to leave unspoken while studying observable evidence. The Ritual and Social Identity feature gives the applicable observance and its complete benefits; this guidance adds no additional ritual reward.
Example of Play
Whisperglass Trace provides an observable clue and can trigger Summation when it is your first leveled Sigilwright spell of the encounter. Shade Decoy protects an exit, but its Reaction-free protection does not make you invisible. Mirror of the Unsaid requires the protected creature’s Reaction, while Unseen Variable requires yours; Veilbound Echo instead competes directly for your Reaction. Their printed saves and truesight exceptions remain intact.
Additional Rules
Table Preference.
Summation is understanding, not a spendable point pool. Its first leveled spell per encounter still grants only its normal 1 Arousal; subclass spellcasting triggers explicitly use that gain instead of duplicating it. Optional later gains represent deliberately accepting further magical instability. Features that prevent an Arousal increase do not count as having gained it. Resolve one reroll of a given save through Greater Summation or Summation Mastery; these subclass features add no rerolls or recovered uses. Arousal gains observe the website’s limit of 3 per turn. Pressure lost through a Climax is not preserved for threshold checks.
Only your own Climax grants your Perfection. Use the parent class’s mode-appropriate Perfection benefit and next-spell deadline, then apply subclass riders at their stated timing. Another creature’s Climax does not grant you Perfection. Resolve the applicable Climax Effect, reduce Libido by 1 where tracked, reset Arousal to 0, then check Depletion. These features grant no universal healing or automatic Exhaustion; use the current Climax Effect and Depletion rules.
Play Modes and Desire Resolution
Classic Play. Use the baseline feature and any expressly stated Classic alternative, without Arousal or Libido. A feature that only modifies Desire has no additional Classic effect.
Veiled Play. Use the baseline and the feature’s Veiled paragraph. Add each stated Arousal gain to the creature’s current total; never assign Composed, Stirred, or Overwhelmed or replace its existing pressure. Resolve Climax immediately at 6. Do not use the Unveiled paragraph.
Unveiled Play. Use the baseline and the feature’s Unveiled paragraph, together with the website’s full Arousal, Libido, Climax, and Depletion rules. Do not inherit the Veiled paragraph. A Libido expenditure requires enough Libido to pay it. Spending the final point does not disable benefits without a Libido cost.
Each feature retains its stated actions, targets, duration, resource costs, and recharge. Changing play modes restores no uses. A gain-dependent benefit requires the Arousal actually to be gained. Unless explicitly excepted, a creature gains at most 3 Arousal per turn; reductions cannot go below 0. Resolve Climax before continuing a feature or applying any after-Climax benefit: the applicable Climax Effect, 1 Libido loss where tracked, Arousal reset to 0, then applicable aftermath triggers. Healing and Exhaustion occur only when an applicable rule grants or imposes them. An EROSave is the creature’s choice of Constitution or Wisdom saving throw, including proficiency only if proficient in that save. Basic Desire Actions retain their one-per-round limit unless an explicit feature overrides it.
Unless a feature expressly states otherwise, this subclass’s EROSave DC is 8 + PB + your Intelligence modifier. PB means proficiency bonus.
Deity Alignment
Some shadow scholars find affinity with Delavira through observation, veils, and deliberate separation, or Cyrillith through masks and the changing presentation of identity. These associations confer no authority over another person’s secrets and require no worship.
Sigilwright class · School of Living Equations · School of Carnal Geometry · Subclass directory · Mechanics of Desire
Grimoire and discipline interactions. Traditional Fifth Edition schools remain unchanged. Discipline-specific riders above apply in all three play modes unless a mode is expressly named. Apply baseline spell text and only the chosen mode’s printed spell option; Veiled and Unveiled alternatives do not stack. A spell’s optional Arousal gain is separate from Summation’s first leveled casting trigger; apply each actual trigger once and respect the shared limit of 3 Arousal per turn. Cantrips never trigger Summation or the leveled-spell riders above, even when their own printed effects can grant Arousal. Summation is not spent. Perfection affects only its permitted rolls and deadlines; it does not automatically maximize a subclass ward’s reduction die or an Unseen Variable die. A later save made against a continuing spell does not count as casting it again. Optional Lunar Resonance remains separately limited by its own rules, with only one lunar benefit per casting.
