About Chronicle Codex

Why this exists

Building a balanced monster by hand is a slog. You pick a challenge rating, cross-reference the damage and hit point tables, work out an offensive rating and a defensive rating, average them, and discover you have landed two CRs off what you wanted. Then you adjust the hit points and start again.

Doing that once is fine. Doing it for every creature in an encounter, the night before a session, is how prep time disappears. And the frustrating part is that it is all just arithmetic — a computer should be doing it.

There were tools out there, and some of them were good, but each one solved a single slice of the problem. One made a stat block and handed it back as an image. Another calculated CR but had nowhere to keep the result. Nothing remembered what I had made last week, and nothing knew that the custom spell I had just written was meant to be cast by the lich I had built an hour earlier.

What I was actually after

Four things, which is why the site is shaped the way it is:

• Show me the maths while I work. The challenge rating updates as you build, not after you submit. If a trait pushes a creature out of the range you wanted, you find out immediately, while it is still easy to change.
• Let the pieces talk to each other. A spell you write shows up in the Monster Creator's spell picker. A monster you build drops into Campaign Forge's combat tracker. That connection is the whole point, and it is the thing single-purpose tools cannot do.
• No signup wall. Everything core works before you make an account, saved in your own browser. Make an account when you want your work on another device, not before.
• Support both rule sets properly. Plenty of tables are still running 2014 rules and plenty have moved to 2024. The edition toggle is a real switch that changes the stat block format and the underlying maths, not a cosmetic label.

What's here now

• Monster Creator — a guided wizard covering ability scores, defences, multiattack, spellcasting, legendary, mythic and lair actions, regional effects and structured lore prompts, with challenge rating calculated as you go.
• Spell Creator — level, school, components, casting time, range, damage, saves and higher-level scaling. Your spells appear alongside the SRD list everywhere a spell can be chosen.
• Campaign Forge — somewhere to keep NPCs, locations, factions, items and quests, with a mind map for how they connect, plus a combat tracker, loot tracker and campaign calendar for use at the table.
• Community Gallery — browse, rate and remix what other DMs have published, and share your own. Every published creation gets its own page, credited to the person who made it.

It is still being built. Things change, and some corners are rougher than others — if you hit one, I would genuinely like to hear about it.

How it stays free

The tools are free to use and I intend to keep them that way. Making an account adds cloud saving so your work follows you between devices.

Paid options are still being worked out, and I would rather say that plainly than put up a pricing page full of promises. Whatever ends up behind a subscription, the parts you need to build a monster and run a session will not be. I am also not going to put adverts in the middle of the creation wizard — nobody needs a banner between step four and step five.

Where the content comes from

The rules content is built on the D&D System Reference Document, which Wizards of the Coast publishes under a Creative Commons licence. That is what makes it legitimate to build on, and the required attribution is on the attribution page. Chronicle Codex is an independent project and is not affiliated with or endorsed by Wizards of the Coast.

Community submissions belong to the people who wrote them. They are credited on their own pages, and anyone can ask for their work to be taken down. I do not scrape artwork from other sites or other tools — if art appears on a creation, it was uploaded or generated by the person who made it.

Get in touch

If something is broken, if the challenge rating maths disagrees with your reading of the rules, or if there is a feature you keep wishing existed, tell me. Bug reports from people actually running games are the most useful thing I get, and they tend to get fixed quickly.