The Fold

The Fold is a book by Zitona Malady which supposedly revolutionizes working mathemagical theory. Its exact contents are unknown, but it apparently allows Zitona to create portals or pathways between distant locations. The book is written in the Halfling language, but is filled with arcane notation that requires additional knowledge to comprehend.

There are many different topics covered in The Fold. Each topic grants understanding about a different aspect of the universe, which can be used to develop new technologies, including spells. To learn about one of the topics in The Fold, a character must typically have an understanding of one or more basic mathematical fields. They must then study the topic in-depth, usually with a tutor. Once the topic has been learned, the character can finally attempt to develop new spells.

Basic Mathematics

These basic mathematical concepts are not covered in The Fold, but must be learned in order to understand anything in The Fold. These are all covered in Caleb's Primer on Mathematics. To learn a topic, a character must spend 8 hours of study with a source of information (a primer or a tutor) and succeed on a DC 15 Intelligence (Arcana) check. On a failure, the character must start the 8 hours again.

• Linear Algebra (learned by Marto)
• Calculus (learned by Marto)
• Statistics
• Category Theory

Topics

The following topics are covered in The Fold. To learn a topic, a character must spend one week of study with a source of information (The Fold or a tutor) and succeed on an Intelligence (Arcana) check. The DC of each topic is given in its listing, along with its prerequisite mathematical bases.

• Water and Sky Field Equations (Requires: Linear Algebra, Calculus, DC 20). A set of complicated equations used for advanced physical Folds, often involving multiple planes of existence.
• Metacosmology (Requires: Linear Algebra, DC 18). The study of the planes of existence and their relationships.
• Probability Folding (Requires: Statistics, DC 17). Manipulating statistics using the principles of The Fold.
• Electromagnetic Quanta and Relativity (Requires: Linear Algebra, Calculus, DC 18). Used in many illusions and manipulations of light.
• Information Theory (Requires: Statistics, DC 17). Used in divinations.
• Theory of Computation (Requires: Category Theory, Statistics, DC 18). Used in programmable spells and divinations.
• Meteorology (Requires: Statistics, DC 19). Used in spells that manipulate weather.
• Sanderson's Laws (Requires: Category Theory, DC 19). Laws related to arcane magic. Used in a lot of spells that manipulate magic directly.
• Formulation of Energy (Requires: Calculus, DC 18). Used in a lot of spells related to creation.
• Quantum Folds (Requires: Statistics, Linear Algebra, DC 18). Used in many spells related to teleportation.
• Temporal Folds (Requires: Calculus, DC 15). Used in spells related to time. The Fold is especially clear and concise in this area.
• Energy Folds (Requires: Calculus, DC 16). Used in spells that manipulate energy.
• Physical Folds (Requires: Caluclus, DC 16). Used in simple spells related to moving matter.*
• Precedent (Requires: DC 20). A confusing topic that just seems to be a list of laws and equations.
• Cognition Models (Requires: Category Theory, DC 18). Models of the mind and soul.

Spells

The following is a list of spells that can be developed by a character with good knowledge of The Fold. Developing a spell follows the same rules as copying a spell from a scroll to a spellbook, except no scroll is necessary as long as the prerequisites are met, and the spells do not need to be on your spell list. Instead, the character must succeed on an Intelligence (Arcana) check, wasting time and materials on a failure. The DC is equal to 14 + the spell's level.

Level 1

• Bless (Probability Folding)
• Create or Destroy Water (Meteorology)
• Expeditious Retreat (Temporal Folds)
• Jump (Temporal Folds, Physical Folds)
• Magic Missile (Energy Folds)
• Silent Image (Electromagnetic Quanta and Relativity)

Level 2

• Blur (Electromagnetic Quanta and Relativity)
• Gentle Repose (Temporal Folds)
• Hold Person (Temporal Folds)
• Invisibility (Electromagnetic Quanta and Relativity)
• Levitate (Physical Folds, Precedent)
• Mirror Image (Metacosmology)
• Misty Step (Quantum Folds)
• Magic Aura (Sanderson's Laws)
• See Invisibility (Electromagnetic Quanta and Relativity)
• Silence (Physical Folds, Precedent)

Level 3

• Blink (Water and Sky Field Equations)
• Clairvoyance (Electromagnetic Quanta and Relativity, Information Theory)
• Counterspell (Sanderson's Laws)
• Dispel Magic (Sanderson's Laws)
• Fly (Physical Folds, Precedent)
• Haste (Temporal Folds)
• Tiny Hut (Physical Folds, Water and Sky Field Equations)
• Major Image (Electromagnetic Quanta and Relativity)
• Nondetection (Electromagnetic Quanta and Relativity, Sanderson's Laws)
• Slow (Temporal Folds)

Level 4

• Banishment (Water and Sky Field Equations)
• Dimension Door (Quantum Folds)
• Fabricate (Formulation of Energy)
• Freedom of Movement (Physical Folds)
• Greater Invisibility (Electromagnetic Quanta and Relativity, Sanderson's Laws)
• Hallucinatory Terrain (Electromagnetic Quanta and Relativity)
• Secret Chest (Water and Sky Field Equations)
• Private Sanctum (Water and Sky Field Equations, Sanderson's Laws)

Level 5

• Creation (Formulation of Energy)
• Hold Monster (Temporal Folds)
• Mislead (Electromagnetic Quanta and Relativity, Quantum Folds)
• Passwall (Quantum Folds)
• Telepathic Bond (Cognition Models)
• Scrying (Electromagnetic Quanta and Relativity, Information Theory)
• Seeming (Electromagnetic Quanta and Relativity)
• Telekinesis (Physical Folds)
• Wall of Force (Energy Folds)

Level 6

• Arcane Gate (Water and Sky Field Equations)
• Contingency (Theory of Computation)
• Instant Summons (Information Theory, Quantum Folds)
• Forbiddance (Sanderson's Laws, Theory of Computation)
• Globe of Invulnerability (Sanderson's Laws)
• Magic Jar (Sanderson's Laws, Water and Sky Field Equations, Cognition Models)
• Move Earth (Physical Folds)
• Programmed Illusion (Electromagnetic Quanta and Relativity, Theory of Computation)
• True Seeing (Sanderson's Laws, Electromagnetic Quanta and Relativity)
• Word of Recall (Theory of Computation, Quantum Folds)

Level 7

• Etherealness (Metacosmology, Water and Sky Field Equations)
• Forcecage (Energy Folds)
• Mirage Arcana (Electromagnetic Quanta and Relativity)
• Magnificent Mansion (Physical Folds, Water and Sky Field Equations)
• Plane Shift (Water and Sky Field Equations, Metacosmology)
• Reverse Gravity (Physical Folds, Precedent)
• Sequester (Sanderson's Laws, Water and Sky Field Equations, Physical Folds)
• Simulacrum (Metacosmology)
• Teleport (Quantum Folds)

Level 8

• Clone (Metacosmology)
• Control Weather (Probability Folding, Meteorology)
• Maze (Water and Sky Field Equations, Sanderson's Laws, Physical Folds)
• Telepathy (Cognition Models)

Level 9

• Astral Projection (Metacosmology, Water and Sky Field Equations)
• Foresight (Probability Folding, Theory of Computation)
• Gate (Water and Sky Field Equations)
• Imprisonment (Water and Sky Field Equations, Sanderson's Laws, Physical Folds)
• Time Stop (Temporal Folds)