Everdraft Compendium of Brilliant Works
Built by a forgotten arcanomechanist who believed no design was ever truly finished, the Everdraft Compendium of Brilliant Works rewrites its own pages each dawn — old schematics shifting, marginalia updating itself in cramped, enthusiastic script. Every owner who has attuned to it has left something behind: a formula on page 34 that wasn't there before, a sketch of a lever-and-spring mechanism between chapters, a single underlined word reading 'better.' It does not judge unfinished work; it simply leaves space for more.
Mechanics
A self-updating tome of invention that lets its wielder build, refine, and deploy brilliant mechanical constructs while pushing the boundaries of what magic and craftsmanship can achieve together.
Living Schematics
This tome contains 8 charges and regains 1d6+2 expended charges daily at dawn. While attuned, you may spend 1 hour studying the tome (which can be done during a short or long rest) to inscribe one new schematic — a record of a spell of 5th level or lower from any class's spell list. The tome can hold up to 6 schematics at a time. Once per turn when you cast a spell from the tome's schematics, you may roll a d6; on a 5 or 6, you do not expend a spell slot for that casting. All other casting rules and components apply normally.
Iterate and Improve
When you cast a spell that deals damage, you may expend 1 charge to add a Refinement Die to the damage roll. Roll a d10; this die explodes — if it shows its maximum value (10), roll it again and add the result, continuing until the die shows less than its maximum. You may use this ability once per turn.
Chassis Override
As an action, you may expend 3 charges to cause the tome to extrude a Medium mechanical construct — the Prototype Frame — in an unoccupied space within 30 feet of you. The Prototype Frame has AC 18, hit points equal to three times your proficiency bonus multiplied by 5 (e.g. 90 HP at proficiency bonus +6), immunity to poison and psychic damage, and acts immediately after your turn in initiative. On its turn it can move up to 40 feet and make one melee attack (+10 to hit, dealing 3d8+5 bludgeoning damage) or one ranged attack in the form of a pressurized bolt (+10 to hit, 60/180 ft., 2d10+5 piercing damage). You direct its movement and actions using a bonus action on your turn. It disappears after 1 minute, when reduced to 0 hit points, or when you dismiss it as a free action. Only one Prototype Frame may exist at a time.
Perpetual Curiosity
When you or an ally you can see within 60 feet fails an Intelligence (Investigation), Intelligence (Arcana), or Intelligence (History) check, you may expend 1 charge as a reaction to allow that creature to reroll the check with advantage, using the new result. You may use this reaction after seeing the result of the original roll.
Enduring Craft
Anything worth doing is worth doing right. Once per dawn, when you finish a short rest, you may designate one object you crafted or one magic item you are attuned to (other than this tome). Until the next dawn, that item or object has its saving throw DCs increased by 2 (if applicable) and any damage it deals ignores resistance — but not immunity.
8 charges
Recharges 1d6+2 at dawn
DM Notes
Balance considerations: The Living Schematics feature is powerful but requires significant investment — 1 hour per schematic and only 6 slots, so the attuned player must curate their library carefully. The 1-in-3 chance to not expend a spell slot is meaningful over a long adventuring day but never guaranteed. Iterate and Improve's exploding d10 is the item's highest-variance feature; at legendary tier this is appropriate, but the DM should be prepared for occasional very large damage spikes (statistically rare but possible). Chassis Override costs 3 of 8 charges for a durable, versatile construct — this is intentionally significant to prevent it from being deployed casually in every fight; a party that burns into it early will feel the charge drain. Enduring Craft's resistance-piercing is the most powerful passive benefit and applies to a single crafted item or attuned item, so it rewards intelligent item selection rather than blanket boosting. Recommend introducing this item at the start of a dungeon-level arc where multiple short rests are available, allowing the schematic-writing mechanic to shine. The tome's physical nature means it can be lost, stolen, or destroyed — ensure the narrative treats it as a precious artifact rather than a background tool.
Generated with: Level 17 · Artificer · Artillerist · A theme that fits her character · Heroic · Legendary · No curses