TEXT: Logical Spells | EN World EN5idEr
  M
  any view arcana as an 
  untamable force that can 
  never truly be known, but those 
  more learned know better, seeing 
  it instead as an almost infinitely 
  complex system that can slowly be 
  learned and mastered. The most 
  powerful spellcasters understand 
  there is a difference between the 
  virtually infinite and truly infi-
  nite—the virtually infinite can one 
  day perhaps be conquered. While 
  earlier 
  mages 
  almost 
  certainly 
  touched upon the idea, it was 
  the cultist-savants known as the 
  Esoteres who codified the idea that 
  magic was a set of logical rules 
  (albeit incredibly difficult for a 
  mortal mind to follow). Like gravity 
  or thermodynamics, by under-
  standing the underpinning forces 
  of the supernatural one can learn to 
  fully take advantage of them. 
   
  WRITING Quin Callahan 
   
  COLOR ART Phil Stone
   
  EDITING Mike Myler
   
  LAYOUT Frank Michienzi
  Logical Spells
  
  Logical Spells | EN World EN5idEr
  Open Game Content | The game rule information in this 
  article is designated Open Game Content. All other material 
  in this article, including maps and illustrations (including 
  illustrations in the public domain), in-character and out-of-
  character narrative and descriptive text, character and place 
  names, trade dress, “EN Publishing,” “EN World,” “EN5ider,” 
  EN Publishing product and article titles, and  
  EN World and EN Publishing logos, are designated 
  Product Identity.
  However the Esoteres—with their ever more inhuman 
  features and various mutations vaguely hidden under 
  simple gray robes, dwelling in their tesseract fortress 
  plotting and waiting by some alien design—should 
  never be trusted. Even so, the benefits of their magic 
  are sometimes undeniable and, for a price, they do 
  offer some of their spells to outsiders. Below are just 
  some of the arcana they might sell and it can only be 
  imagined what might not be available for purchase. 
  Measure
  Divination cantrip (sorcerer, warlock, wizard)
  Casting Time: 1 action
  Range: 120 feet
  Components: V
  Duration: Instantaneous
  Upon casting this spell, you choose an area of up to 
  40 cubic feet that is within range. You instantly deter-
  mine the height, width, diameter, weight, temperature, 
  or similar measurement of an object, group of objects, 
  or similar collection of objects (like the volume of 
  a patch of soil or pool of water) that are within the 
  area. The spell cannot handle extremely precise or 
  large measurements. For example, measure cannot be 
  used to measure the exact weight of a grain of sand, 
  or to determine the width of an odd non-euclidian 
  object or similarly strange magical occurrences. In 
  addition, the spell always fails when cast inside of a 
  pocket dimension (such as those of a Portable Hole 
  and similar items). 
  A creature knows when measure is cast on them or 
  objects on their person, including when it is only a part 
  of a wider area or group of objects being measured. 
  The creature may make a Charisma saving throw to 
  resist the spell, being excluded from the result on a 
  successful save. Creatures of Intelligence 3 or lower 
  automatically fail this saving throw. 
  Detecting Counterfeit. This spell may cause certain 
  acts of trickey, such as attempts to pay with fake money, 
  to instantly fail unless the deceiver has accounted for 
  the proper weight of genuine coinage, or  grant advan-
  tage on an Intelligence (Investigation) check opposed 
  by the buyer’s Charisma (Deception) check to realize 
  that the currency is counterfeit.
  GM NOTE
  The Esoteres charge a minimum of 75 gp per spell 
  level for the privilege of copying their magics, in 
  addition to the standard cost of scribing a spell. 
  Acquiring any of the following spells of 5th level 
  or higher requires a far more interesting payment 
  than gold, as determined by the GM (magical items, 
  memories, or even the color of one’s eyes are not 
  unheard of prices to pay).
  GM NOTE
  Using the calculate cantrip allows a player to make 
  use of a calculator at the table in order to rapidly 
  answer mathematical equations
  Cantrips
  Calculate
  Divination cantrip (sorcerer, warlock, wizard)
  Casting Time: 1 action
  Range: Self
  Components: V, S
  Duration: Instantaneous
  You instantly know the answer to a mathematical 
  equation that you speak aloud. The equation must be 
  a problem that a creature with Intelligence 20 could 
  solve using nonmagical tools with 1 hour of calcula-
  tion, otherwise the spell fails.
  
  Logical Spells | EN World EN5idEr
  Level 1
  Searing Equation
  1st-level enchantment (warlock, wizard)
  Casting Time: 1 action
  Range: Self (15-foot cone)
  Components: V, S
  Duration: Instantaneous
  This spell causes you to briefly go into a magical 
  trance and whisper an alien equation which you never 
  fully remember once the action is complete. Each 
  creature in a 15-foot cone must make an Intelligence 
  saving throw. A creature takes 3d4 psychic damage 
  and is deafened for 1 round on a failed save, or half as 
  much damage on a successful one. In addition, at the 
  end of its turn a creature deafened by this spell takes 
  1d4 psychic damage. 
  Creatures who are unable to hear the equation, 
  immune to psychic damage, or who have an Intelli-
  gence score lower than 4 are immune to this spell. 
  At Higher Levels. When you cast this spell using a 
  spell slot of 2nd level or higher, creatures are deafened 
  for one additional round for each slot level above 1st.
  Level 2
  Ricochet
  2nd-level divination (bard, sorcerer, warlock, wizard)
  Casting Time: 1 action
  Range: Touch
  Components: V, S
  Duration: Concentration, up to 1 minute
  You touch up to 10 pieces of nonmagical ammuni-
  tion. Until the spell ends, when the ammunition is 
  used to make a ranged weapon attack against a crea-
  ture behind cover, as long as there is an unobstructed 
  path between the attacker and the target of their 
  attack the creature does not gain any bonuses to AC 
  granted by its cover. This does not grant the attacker 
  any bonuses against invisible targets.
  At Higher Levels. When you cast this spell using 
  a spell slot of 4th level or higher, on a successful hit 
  the ammunition can bound off of a creature and rico-
  chet into another target for each two slot levels above 
  2nd. The new target of this ricochet must be within 30 
  feet of the ammunition’s previous target. The attacker 
  makes a ranged weapon attack roll against each target 
  of a ricocheted piece of ammunition, with all attack 
  rolls off a ricochet made with disadvantage.
  Level 3
  Non-Euclidean Flash
  3rd-level enchantment (warlock, wizard)
  Casting Time: 1 action
  Range: 60 feet
  Components: V, S
  Duration: Instantaneous
  You bombard the mind of creature within range 
  and fill it with thoughts of strange and impossible 
  shapes. The target must make an Intelligence saving 
  throw. On a failed save, it takes 4d8 psychic damage 
  and is stunned until the start of your next turn. Crea-
  tures immune to psychic damage are unaffected by 
  this spell.
  GM NOTE
  Certain real life terms such as ‘Euclidean’ can present 
  unique challenges when trying to integrate them into 
  a fantasy world because they are named after people 
  or places in Earth’s history. While Euclid was a real 
  Greek mathematician, it is usually very easy for a GM 
  to either establish there was an ancient scholar with 
  the same name who made similar discoveries or to 
  simply switch out ‘Euclidian’ with a term appropriate 
  to their own world’s lore. 
  
  Logical Spells | EN World EN5idEr
  Level 5
  Cube
  5th-level conjuration (wizard)
  Casting Time: 1 action
  Range: 120 feet
  Components: V,S
  Duration: Concentration, up to 1 minute
  A perfect 10-foot cube appears in an unoccupied 
  space of your choice within range and lasts for the 
  duration. This space can be in midair, if you so desire. 
  The cube is black and completely non-reflective. Any 
  creature that ends its turn within 5 feet of the cube 
  must make an Intelligence saving throw, taking 5d6 
  psychic damage on a failed save, or half as much 
  damage on a successful one. 
  As a bonus action, you can move the cube up to 10 
  feet in any direction, so long as the space it will end on 
  is within your line of sight. The cube cannot be made 
  to pass through other creatures, although a creature 
  may choose to pass through the cube on its own turn. 
  Entering the space the cube occupies forces a creature 
  to make an Intelligence saving throw. The creature 
  takes 5d6 psychic damage on a failed save, or half 
  as much damage on a successful one. This damage 
  does not prevent the creature from taking additional 
  damage if it ends its turn within 5 feet of the cube.
  A construct must succeed on a Wisdom saving 
  throw when attempting to pass through the cube. On 
  a failure, it cannot pass through the cube. On a success, 
  it may pass through the cube (and will then imme-
  diately need to make an Intelligence saving throw as 
  normal, unless it is immune to psychic damage).
  Level 7
  Angel Paradox
  7th-level evocation (wizard)
  Casting Time: 1 action
  Range: 30 feet
  Components: V
  Duration: 7 days
  A non-celestial creature within range is bombarded 
  with a fraction of energy stolen from some slum-
  bering, deific source, immediately taking 40 radiant 
  damage. This spell ignores resistances but does not 
  ignore immunities. A creature killed by this spell 
  does not decay and cannot become undead for the 
  spell’s duration. Days spent under the influence of 
  this spell don’t count against the time limit of spells 
  such as raise dead. This effect ends early if the corpse 
  takes necrotic damage.
  Level 9
  Recursive Descent
  9th-level enchantment (wizard)
  Casting Time: 1 action
  Range: 30 feet
  Components: V, S
  Duration: Instantaneous 
  Choose one creature within range. It must succeed 
  on an Intelligence saving throw or be immediately 
  stuck in a millisecond long recursive memory loop. 
  Creatures with an Intelligence score greater than 24 or 
  immunity to psychic damage are immune to this spell. 
  A target affected by this spell is incapacitated, can’t 
  move or speak, and is unaware of its surroundings. It 
  drops whatever it’s holding, and it automatically fails 
  Strength and Dexterity saving throws. Attack rolls 
  against the target have advantage, and any attack that 
  hits it is a critical hit if the attacker is within 5 feet. 
  In addition, the target cannot be charmed, frightened, 
  or take psychic damage thanks to the mental stasis 
  caused by this powerful curse. 
  Casting greater restoration on an affected target 
  releases it from this spell’s effect for 24 hours, at which 
  point the curse resumes (no additional saving throw). 
  You can use a bonus action to release the target, but 
  otherwise without the intervention of a deity or simi-
  larly powerful entity this effect can only be ended 
  through the use of a wish spell, dispel magic (with an 
  ability check made with disadvantage if cast using a 
  spell slot of 8th level or lower), or by the affected crea-
  ture’s death. e
  
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