Product overview

See Mimir working.

A worldbuilding tool should be easier to understand by watching it than by reading a feature list. Follow one connected world through entries, relationships, trees, timeline, map, Mimir AI and Proving Grounds.

Reserved for a recording of the current beta build using one consistent demo world.

01 Create and connect02 See the world03 Ask and review04 Test in Proving Grounds

Your world is bigger than a pile of notes.

Complex worlds should become clearer as they grow.

Pages are useful, but a world is made from the relationships between them. Mimir connects characters, places, cultures, factions, events and stories so you can move from a detail to the wider world around it.

See the same canon through trees, timelines, maps, backlinks and relationships. Build worlds, not documents.

Family or relationship tree using real world data.

One canon understood chronologically and spatially.

A real answer with the supporting canon shown alongside it.

A real refusal to fill an unsupported gap in the world.

Mimir AI

Ask your world. Get an answer grounded in your world.

Mimir is not there to make up your canon for you. It retrieves relevant lore, answers from material you have actually written and should make uncertainty visible rather than filling gaps with confident invention.

Question: Who killed King Aldric?
Mimir: There is no confirmed killer in your current canon. Three entries implicate House Vael, but none state that they carried out the assassination.

This example explains the intended behaviour. It is not presented as a product screenshot.

Explore Mimir AI

Lore Consistency Review

Find contradictions before your audience does.

Run a review across the canon to surface conflicting dates, incompatible relationships, duplicate facts, broken references and other issues that become difficult to spot as a world grows.

Reserved for a real contradiction with a clear path to review it.

Reserved for a working simulation, not an empty setup screen.

Proving Grounds

Don't just document your world. Test it.

Prototype conversations, quest logic, tabletop sessions, board-game ideas and other interactive scenarios before they become canon. Use the world you have already built as the context for testing what happens next.

Explore Proving Grounds

Migration is part of Core

Bring your existing world with you.

You don't have to abandon five years of worldbuilding to move to Mimir. Import ordinary files and supported projects, review what Mimir found before creating draft entries, then continue working in a local Mimir world.

1Select sourceChoose a verified spreadsheet or document format.

2Review mappingInspect fields or extracted proposals before creating entries.

3Open local worldContinue in readable Mimir files under your control.

Migration remains part of Core because keeping your work is not a premium privilege.

Explore Migration

Collaboration and hosting

Build together without making everyone a power user.

Writers can share a collaborative workspace. Game Masters can host the world while players join as viewers or controlled participants using Mimir Core. Permissions decide what each person can see and change.

Mimir is not a public social network or a place to meet strangers. It is built for work with the collaborators, friends and players you already know.

Future power-user capture with private information visible.

The same world with spoilers and private fields hidden.

For Worldbuilders

Built for worldbuilders, whatever form the finished world takes.

One connected world can move between writing, play, design and production as your project changes.

01

Game Masters

Build campaigns, hide spoilers, connect factions and histories, test quests and sessions, then host the world for your players.

02

Writers & screenwriters

Track chronology, families, cultures, canon and narrative arcs while keeping the source files under your control.

03

Game developers & narrative designers

Keep world and narrative data structured, test state and dialogue logic, and maintain one canonical source of truth.

Reserved for Mimir beside its corresponding local files.

Local-first by design

Your world belongs to you.

Your core world lives locally in readable files. You can use the local foundation offline. Cancelling or downgrading does not erase the world you created or lock you out of your own files.

Unlimited local worlds and entries across every tier.
Migration and export are not premium privileges.
Local work survives a downgrade.

Network functionality such as Mimir AI, hosted collaboration and hosted worlds necessarily transmits the selected data needed to provide that feature. Production subprocessors and retention details will be published once verified.

Planned V1 pricing

Pay for capability, not permission to keep your world.

Every tier includes unlimited local worlds and entries. Paid plans add deeper workflows, larger Mimir AI allowances, collaboration and hosted scale.

These are the planned V1 prices. Mimir is currently in alpha and paid checkout is not live.

Mimir Core

Build your world

£0 / forever

Unlimited local worlds and entries
Standard worldbuilding editors and visual tools
General imports and competitor migration
Standard and safe-to-publish export
Core monthly Mimir AI allowance
Join invited collaborative or hosted experiences

Join the beta

Apprentice

Develop your world

£6.99 / month

or £69.99/year

Everything in Mimir Core
Custom Schema Editor
Narrative Planner and advanced tree/filter tools
Create and run Proving Grounds locally
Small collaborative workspace
Larger Mimir AI allowance

Join the beta

Worldsmith

Bring your world to life

£14.99 / month

or £149.99/year

Everything in Apprentice
Lore Consistency Review and AI Context Bundles
Simulation and world-state tools
Live collaborative Proving Grounds hosting
Hosted participant worlds
Expanded collaboration and Mimir AI allowance

Join the beta

Loremaster

Work at professional scale

£24.99 / month

or £249.99/year

Everything in Worldsmith
More hosted worlds
More collaborators and participants
More hosted storage
Larger Mimir AI allowance
Priority support queue

Join the beta

What never becomes a premium privilege.

Unlimited local worlds and entries

Your own files are not a metered cloud resource.

Migration and export

Moving in and taking your own work out stay accessible.

Core participants can join

A host can be the power user without requiring every player to subscribe.

Local work survives a downgrade

Premium operations may pause, but local content is not erased.

MCP connections and direct Unreal, Unity and Godot workflows are future roadmap items, not V1 promises.

See the roadmap

FAQ

Common questions

: Mimir is for worldbuilders. Game Masters and Dungeon Masters are a major launch audience, alongside writers, screenwriters, narrative designers and game developers. It is one product for connected worlds.
: Yes. Core is intended to remain a useful local product with no time limit and no local world or entry caps. Paid plans add advanced workflows, larger Mimir AI allowances, collaboration and hosted scale.
: Your local world data remains yours and stays readable. A downgrade can disable premium creation, AI, collaboration or hosted operations, but it does not delete local work. Exact hosted-resource grace rules will be published before hosted billing opens.
: Yes. General imports and competitor migration are part of Mimir Core because changing tools should not require abandoning years of worldbuilding.
: The local worldbuilding foundation works from files on your machine. Mimir AI, live collaboration and hosted worlds require a connection. Losing connectivity does not remove access to the local copy.
: Yes. Invited players can use Mimir Core to join appropriate hosted experiences, subject to the host's permissions and capacity.
: No. Mimir is not designed for open stranger chat, direct messages or public discovery. Collaboration and hosting are for people you choose to invite.
: They are post-V1 roadmap items. Shieldwall plans feedback and refinement after V1 before MCP connections and direct Unreal, Unity and Godot workflows.
: Ordinary local creation and editing use files on your device. Mimir AI, hosted collaboration and hosted worlds necessarily transmit selected data needed to provide them. Verified subprocessors and retention details will be published before public launch.

Early access

Join the beta.

Be among the first worldbuilders to use Mimir, help Shieldwall find friction before public launch and receive launch updates.

JavaScript is required to load the signup form. You can instead email alexander.goldsmith@shieldwallgames.co.uk.

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