UNIVERSE — _{(Alternate Universe, AU, World): A self-contained reality which is distinct from other realities. separated by a universal membrane. All known forms of life come to exist within these pockets of reality, and most never leave.}

ALTERNATE TIMELINE — _{(AT): A branching separation of reality that — if sufficiently stable and independent — will eventually split off and form its own independent universe. It's currently theorized that all universes were once ATs.}

MULTIVERSE — _{Any collection of distinct universes which itself is distinct from other collections, made separate by a multiversal wall. Cannot be traversed by normal means.}

PRIME _{— (OG, The Multiversal Nucleus): The first universe to develop in any multiverse. The code of PRIME acts as a blueprint for all future universes in that multiverse, which will continue to diverge more as they are born farther away.}

MULTIVERSE TAU - _{The 19th known multiverse, within which our story takes place. Also known as M-TAU or just TAU.}

(THE) UNDERGROUND - _{A grand system of caverns found under "Mt. Ebott", which serves as home and prison to monsterkind in most AUs. The actual location of "Ebott" — and therefore its respective Underground — varies by universe, which in turn affects monsterkind's culture.}

(THE) CORE - _{A giant thermomagical reactor responsible for supplying the Underground with power. Most versions of monsterkind become dependent on the Core's output to farm the magic-rich crops they need to survive. In many universes, it is an anomalous object, with both "always existed" and "recently invented by the previous royal scientist" being true.}

INCODE - _{An entity which lives inside (or else does not regularly leave) a universe. May also refer to the "living area" (main planetary surface) of a universe predominantly occupied by incodes — I.E.: "an incode world". Incodes are more heavily affected by their own universe's rules and may struggle to understand concepts from outside their own world.}

OUTCODE - _{An entity which lives outside (or else regularly leaves) a universe. May also refer to the "living area" (main planetary surface) of a universe predominantly occupied by outcodes — I.E.: "an outcode world". Almost any sapient being may become an outcode if given the means to leave their original universe, but the longer they remain away, the more their absence will slowly transform them — and the more their world will grow to close the open wound they left behind.}

CODE — _{The information that makes up every piece of reality. Something of a misnomer; "code" is to all aspects of reality what DNA is to living things. (A rock, for example, has only code. A chair, which was once a tree, has both code and DNA.)}

CODE RADIATION — _{A form of non-ionizing particle radiation which is released by decomposing code. Found in great concentrations in the VOID and ANTIVOID, shed from nearby universes and multiverses, respectively.}

CODE MUTATION — _{Mutations to living code caused by extended exposure to code radiation, typically manifesting as physiological changes. If these changes are life-altering, this phenomena may instead be called code corruption. Since most intra-universal travel requires exposure to the VOID, regularly traveling outcodes are at greater risk.}

VOID — _{The space between universes. Levels of radiation vary by the state of nearby universes, but is generally high.}

ANTIVOID - _{The space between multiverses. Extreme code radiation is found throughout.}

THE WAR BETWEEN HUMANS AND MONSTERS — _{(THE WAR, THE GREAT WAR): In most AUs, the deciding event that leads to the imprisonment of monsters under Mt. Ebott. More rarely, it may lead to the imprisonment of humanity or to monsterkind's extinction. The extinction or near-extinction of magi, if applicable to a specific universe, always follows.}

(POST-)PACIFIST/NEUTRAL/GENOCIDE — _{Classifications for the most common ways that monsterkind exits (or does not exit) their respective Underground. Typically triggered and/or brought to fruition by the Catalyst. The actions that bring a "route" to its climax are referred to as a "run"; ie: "doing a neutral run", "post-neutral run", "the neutral route".}

MAGIC-USER — _{Any sapient entity that can consciously burn mana for the use of magic.}

MUNDANE — _{Any entity which cannot use magic or object which does not contain mana.}

HUMAN — _{A sentient ape of the extant species Homo sapiens. Their nature is naturally more matter than mana, which makes them somewhat nonreactive to magic, and more physically resilient than creatures who are adept at magic-use.}

MAGE/MAGUS/MAGI _{⁽¹⁾ — A human born with a physical, genetically-dominant irregularity of the SOUL which allows them to burn mana for the use of magic, especially for the formation of constructs. Magi can be extremely powerful and long-lived, but typically trade this power for lifelong health problems. Also known as an "active" magic-user. ⁽²⁾}

MAGE LINEAGE — _{Any family comprised of more than 90% non-latent magi. ⁽³⁾ Aptitudes for certain abilities typically run dominantly — for example, specializing in healing magic or fire magic, but not both. More specific abilities generally mean greater power but poorer health. By contrast, a "bastard" magus will likely be weaker, but healthier and less limited.}

WITCH _{⁽⁴⁾ — A subset of magus that is capable of limited magic use, but not to such an extent as to be able to form constructs. A magus may "start" as a witch if their abilities take a long time to develop (or else do not awaken naturally); similarly, a magus may once again "become" a witch through sickness, age or injury. Also known as a "passive" magic-user.}

MONSTER — _{Any sapient entity which is not human and has a SOUL. Monster physiology is generally more mana than matter, making them extremely susceptible to magical/emotional influence. Said physiology, however, tends to make them naturally adept at magic use, to such an extent that magic defines their cultures.}

BOSS MONSTER — _{An uncommon subtype of monster which is especially magically powerful and extremely long-lived, with SOULS that can persist after death. Any monster has a small chance to be born as a Boss, which raises significantly if one or both of its parents are Bosses. Some monsters can also temporarily become Bosses under duress.}

HYBRID — _{The offspring of a monster and human. Can only result in one of two possible first-generation hybrids, which will themselves be infertile. Hybrids tend to be more magically adept than the standard magus, but live short lives.}

ALTERNATE — _{Any iteration of a specific (sapient) entity which exists in more than one universe. Alternates born or created closer to PRIME tend to more closely resemble their "original" iteration, or "sourcecode".}

(THE) CATALYST — _{The entity which triggers the inciting events of a universe's timeline, if any exist. Depending on event requirements, the Catalyst is a "role" which can theoretically be filled by any entity. Magi are naturally drawn to it.}

GOD(S) — _{An entity with significant control over a specific force or concept. Typically, such forms of godhood are "roles" that any powerful-enough entity could fill — thus, most gods are capable of dying and being replaced.}

PERSONIFICATION(S) — _{An entity which is the "living embodiment" of a specific force or concept. A personification's existence is inextricably tied to its domain, making the entity impossible to kill without also destroying the concept it represents — or vice versa. They will be responsible for maintaining a balance related to their domain, and may do so unconsciously or by instinct. May also be known as "titans" or "primordial deities". Will always be one of a matching pair.}

primordial organ — _{any of the first superorganisms to develop in an infant multiverse, serving as sort of proto-personifications to regulate one or more of the multiverse's early Balances. The death of a multiverse's primordial organs (and subsequent replacement by the corresponding personifications) marks a multiverse's "adulthood".}

CREATOR(S) — _{Humans who receive limited precognitive visions of entities in other universes, and who may be able to influence limited changes in the worlds they dream of. To avoid potentially cataclysmic feedback, universes suspected to hold Creators are off-limits. Near-copies of creator universes which lack the same influence are called meta universes.}

DESTROYER(S) — _{Entities aiming either to destroy parts of the multiverse, or to spread fear and misery throughout it. Typically outcodes. Their methods and motivations vary. Notably, they are a part of a healthy multiverse's ecosystem.}

MANA — _{A highly volatile form of energy which enables a sapient entity's emotional function, memory and willpower. Only naturally generated within specialized objects known as nuclei — most commonly SOULS or OBJECTS OF POWER.}

MAGIC — _{Any act of consciously burning mana with the intention of altering reality. Many different types of magic exist, loosely grouped under constructs (the conscious condensing of mana into a physical shape) and spells (anything that isn't a construct). Use of the term "spell" is only popular among humans; monsters call the same concept "magic" — IE: "healing spell" (human) vs. "healing magic" (monster). Magic is powerful, but must follow the rules of physical reality.}

BULLET — _{A type of low-mana construct exclusively meant for throwing, typically as a hands-free offensive projectile or communicative tool. Extremely common amongst all types of monster, and thus popular in Encounters.}

BARRIER — _{Any defensive magical construct, typically taking the form of a wall between the magic-user and percieved danger. Barrier spells are a relatively common skill amongst magi, but are almost never practiced to proficiency given the popularity of offensive magics. Monsters cannot create "true" barriers, but can mimic them using lesser constructs.}

ENCOUNTER — _{A form of communication primarily used by monsters, where two entities use magic to isolate themselves from their surroundings and engage in an turn-based mock-battle. Encounters may involve choreographed displays of magic, verbal sparring and controlled hits from bullets, which, under normal circumstances, are not meant to harm.}

(MONSTER) DUST — _{The fine, powdery byproduct left behind after a monster dies. Common funeral rites are to spread the dust over something the monster loved. More rarely, monsters may participate in ritual cannibalism, incorporating dust into food meant to sustain the community. In some AUs, this concept inspires the "supplements" used in hybrid food.}

MONSTER FOOD — _{(Magic food): Food that is either extremely rich in or comprised primarily of mana. Typically created by seeding mana into mundane crop plants — which, unlike animals, can retain most of their rigidity even with high mana content — and then harvesting the resulting produce. Because of this, most versions of monsterkind are vegetarian.}

HYBRID FOOD — _{Physical food (or "human food") with a mana-count that has been artificially raised by the addition of a third-party magical ingredient, such as a dust-based additive. Given that neither species can fully survive on the diet of the other, hybrid food typically serves as a social or accessibility tool, and is not meant to be a dietary staple.}

(OBJECT) OF POWER — _{An object which comes to act as a nucleus to create and store magic like a SOUL would. Extremely rare; typically quite powerful. How they come to be is unknown.}

SOUL — _{The metaphysical organ enabling a sapient creature's memories, emotions and willpower. Produces and stores mana, even if the entity it belongs to is not a magic-user, since mana is necessary for sapience to exist. May carry a color which signifies the entity's dominant trait, if any exist — generally, the more pure this color, the more pure the trait.}

SOUL STATE — _{A type of temporary status effect applied to the SOUL through contact with specialized constructs. Can be helpful or harmful depending on the caster's intentions. Typically, only boss monsters can apply them.}

SOUL SICKNESS — _{Any type of magical malady. Though SOUL sicknesses have long been thought to be exclusively caused by trauma or injury, as more universes see integration between monsters and modern human medicine, there is mounting evidence of a genetic and environmental aspect. Generally poorly understood and difficult or impossible to fully treat.}

SOUL SEX — _{Any form of sexual activity involving the SOULS of two or more sapient entities. This is the primary method of reproduction in monsters, who are typically physically sexless and present next to no distinct sexual dimorphism. (Not to be confused with identity or expression, where monsters may or may not superficially resemble humans.) Because of this, monsters are biological hermaphrodites, with any monster being able to act as carrier or receiver in a pregnancy.}

ECTO-CONSTRUCTS — _{(Ecto, Ecto-flesh): A mild form of magical transmutation where specialized constructs are formed to mimic the sexual characteristics of humans, for use in gender expression or alternative intercourse. Given how mana-intensive they are, casual use is typically limited to bosses. Ecto may also be involved in later stages of SOUL reproduction if the carrying parent needs to manifest a layer of "ecto flesh" to protect and nurture the SOULING.}

STATS — _{Numerical representations of an entity's health or abilities, originally for use in encounters. Average stats vary greatly between different groups, and between the incode and outcode versions of those groups. Popular stats include HP ⁽¹⁾ (Hit Points/Hope), LV (LOVE/Levels of Violence), DF (Defense), AT (Attack), and more rarely MP (Mana Points).}

LEYLINE(S) — _{Invisible tracks which circulate mana through the body. Found in (and are essential to) most living creatures, but are much more prominent in magic-users. For monsters especially, it functions as both the circulatory and nervous system. Damage to a monster's leylines can therefore cause severe and permanent injury and/or disability.}

AURA — _{The exhaust of burned mana as it leaves the body, typically invisible to the naked eye. Auras carry various types of information which, at least to a small extent, most creatures can sense. If an entity is especially sensitive to this information, it is known as an Empath. Empathy as an abiltiy and empathy as an emotional response are not the same.}

DETERMINATION/DT — _{A type of mana which gives an entity, among other things, the will to exist after death. Typically found in high quantities in humans but less in monsters, who are physiologically reactive to it.}

DT ABILITIES — _{Any of a set of powerful, extremely rare magical abilities which can warp the natural world in ways normal magic cannot. The most common of these abilities are the creation of SAVE POINTS, or anchors in an AU's timeline. Generally, the returning to a recent save point — manually or upon death — is called a LOAD, the returning to a universe's first save point is called a RESET, and an extremely localized LOAD may be called a REFUSE.}

BALANCE — _{May refer to the BALANCE OF MAGIC, BALANCE OF LIFE, or the BALANCE OF EMOTION. Any living multiverse requires these forces to remain in balance to survive. Should they fall out of balance, the multiverse will eventually collapse.}