The Brass Mainspring Codex
A brass-bound tactician's grimoire teaches its keeper to recalibrate bodies and objects, then turn a battle by bending an enemy's sense of time and choice.
Spellbook · Level 5 Wizard, School of Enchantment · Level 5
The Brass Mainspring Codex
A brass-bound tactician's grimoire teaches its keeper to recalibrate bodies and objects, then turn a battle by bending an enemy's sense of time and choice.
Ex librisMira VennWizard, School of Enchantment
At a glance
Level
5
Level 5 Wizard, School of Enchantment
Spells
9
1 cantrip, 5 signature
Spell slots
1st level
2nd level
3rd level
At the table
A margin note
Plot hook
Spells
9 spellsCantrips
1- Repairs a single break or tear in an object you touch, no larger than 1 foot in any dimension. The repair leaves no trace of the damage.
- Duration
- Instantaneous
- Target
- One break or tear in an object
- Components
- V, S
- Higher levels
- No effect from higher-level spell slots.
- Source
- Player's Handbook
1st level
3- Touch a creature to increase its speed by 10 feet for the duration.
- Duration
- 1 hour
- Target
- One creature
- Components
- V, S, M (a pinch of dirt)
- Higher levels
- When cast using a spell slot of 2nd level or higher, target one additional creature for each slot level above 1st.
- Source
- Player's Handbook
- Choose up to five falling creatures. Their rate of descent slows to 60 feet per round until the spell ends; if a target lands before then, it takes no falling damage and lands on its feet.
- Duration
- 1 minute
- Target
- Up to five falling creatures
- Components
- V, M (a small feather or piece of down)
- Higher levels
- When cast using a spell slot of 2nd level or higher, target one additional falling creature for each slot level above 1st.
- Source
- Player's Handbook
- Choose one object weighing 1 to 5 pounds within range that is not being worn or carried. It flies in a line up to 90 feet in a direction you choose, stopping early if it impacts a creature or solid object. A creature in its path makes a Dexterity saving throw, taking the damage on a failure; the object continues onward if the creature succeeds. The spell damages the object it strikes.
- Duration
- Instantaneous
- Target
- One unattended object weighing 1 to 5 pounds, launched along a line
- Components
- S
- Save or attack
- Dexterity saving throw
- Damage
- bludgeoning
- Higher levels
- When cast using a spell slot of 2nd level or higher, the damage increases by for each slot level above 1st.
- Source
- Xanathar's Guide to Everything
2nd level
3- Touch a creature and choose one ability. The target has advantage on ability checks using that ability. The spell's Bear's Endurance option also grants advantage on Constitution checks and temporary hit points.
- Duration
- Concentration, up to 1 hour
- Target
- One creature
- Components
- V, S, M (fur or a feather from a beast)
- Higher levels
- When cast using a spell slot of 3rd level or higher, target one additional creature for each slot level above 2nd.
- Source
- Player's Handbook
- Choose a visible creature or an object that is neither worn nor carried. Enlarge increases the target's size by one category, grants advantage on Strength checks and Strength saving throws, and adjusts its weapon damage as described. Reduce decreases its size by one category, imposes disadvantage on Strength checks and Strength saving throws, and adjusts its weapon damage as described.
- Duration
- Concentration, up to 1 minute
- Target
- One creature or an unattended object
- Components
- V, S, M (a pinch of powdered iron)
- Save or attack
- An unwilling creature can make a Constitution saving throw to avoid the effect.
- Damage
- Enlarge: target's weapon attacks deal an extra damage. Reduce: target's weapon attacks deal less damage, to a minimum of 1.
- Higher levels
- No additional effect from higher-level spell slots.
- Source
- Player's Handbook
- A creature you touch becomes invisible, along with anything it is wearing or carrying, until the spell ends or it attacks or casts a spell.
- Duration
- Concentration, up to 1 minute
- Target
- One creature
- Components
- V, S
- Higher levels
- When cast using a spell slot of 3rd level or higher, target one additional creature for each slot level above 2nd.
- Source
- Player's Handbook
3rd level
2- Choose a willing creature. Its speed doubles, it gains a bonus to AC, advantage on Dexterity saving throws, and an additional action on each of its turns. That action can be used only to Attack (one weapon attack only), Dash, Disengage, Hide, or Use an Object. When the spell ends, the target can't move or take actions until after its next turn.
- Duration
- Concentration, up to 1 minute
- Target
- One willing creature
- Components
- V, S, M (a shaving of licorice root)
- Higher levels
- No additional effect from higher-level spell slots.
- Source
- Player's Handbook
- Choose up to six creatures in a 40-foot cube. Each target that fails its Wisdom saving throw has its speed halved, takes a -2 penalty to AC and Dexterity saving throws, and can't use reactions. On its turn, it can use either an action or a bonus action, not both, and it can make only one melee or ranged attack. The spell also limits spellcasting as described in its full rules.
- Duration
- Concentration, up to 1 minute
- Target
- Up to six creatures in a 40-foot cube
- Components
- V, S, M (a drop of molasses)
- Save or attack
- Wisdom saving throw
- Higher levels
- When cast using a spell slot of 4th level or higher, target one additional creature for each slot level above 3rd.
- Source
- Player's Handbook
In the margins
3 notes
FormulaA larger lever is not always a stronger lever. Measure the load, then choose the hinge.
WarningDo not wind the spine while Haste is active. The resulting rhythm is distracting, and I will not explain the incident again.
DiaryThe mind resists less when offered a choice it already wanted to make.
The book itself
The mainspring ticks faster near unstable machinery or magically altered objects.
Its diagrams treat bodies, tools, and battlefield formations as systems whose properties can be recalibrated.
The caster
Wizard, School of EnchantmentMira Venn
Studies: Tactical enchantment and transmutation, with an emphasis on altering physical properties and improving allies' performance.Manner: Precise and courteous, Mira treats every conversation like a negotiation and every fight like a problem in applied mechanics.Focus: A brass stylus used to trace angles in the air, with the codex's ticking mainspring serving as a metronome.Quirk: She counts under her breath whenever someone makes a decision, then taps her stylus twice when they surprise her.Wants: She seeks the missing plans for an ancient mechanism said to alter the physical laws within a battlefield.Mira Venn apprenticed as a clockmaker before studying wizardry. After watching a brilliant commander lose a battle to poor timing, she began recording magic as a system of forces, bodies, and decisions.
The book
A treasured, compact grimoire encased in engraved brass plates. Its ticking mainspring spine clicks softly when opened, while fine diagrams of gears, limbs, and force vectors fill the pages. Brass corners are worn smooth from years of handling.
Its wards · GM only
About the book
FormatBrass-bound mechanical codex
ThemeTransmutation
Written by aLevel 5 Wizard, School of Enchantment
Caster level5
SystemDungeons & Dragons 5th Edition
Plot hooks
1The codex's mainspring has begun ticking in time with a buried engine beneath the city, and its diagrams are changing to show a machine no one remembers building.
2A rival artificer claims the brass plates were stolen from a military research archive and wants the book returned before its tactical enchantments are copied.
3One of the spellbook's old owners vanished after using its calculations to predict a battle that has not yet happened.
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