Mid-game rules questions in Sorcery: Contested Realm tend to end in one of three places: the rulebook PDF, a Discord thread, or — if anyone at the table knows it exists — the Curiosa Codex. It's the publisher's own glossary-and-rulings reference, it lives at curiosa.io/codex, and it gets a fraction of the attention the deckbuilder half of Curiosa does. Search for write-ups about it and you'll find the Codex itself, the publisher's rulebook posts, and not much else.
What follows is the missing write-up: what the Codex is, what's in it, where it sits in the official rules stack, and one real lookup walked start to finish — from "wait, can that happen?" to an answer you can point at.
What the Codex actually is
The Codex is the rules-reference corner of Curiosa, the publisher-operated platform that also hosts the card database and deckbuilder. The whole site, Codex included, is run by Erik's Curiosa Limited, and it sits in the directory's Deckbuilders & Tools section with the rest of the reference utilities. Curiosa's own description calls the page the collection of "glossary terms & rulings" for Sorcery — definitions of the game's terms, plus the deeper rulings that don't fit on a card or in the rulebook's page count.
Structurally it's an alphabetical reference where every entry has its own shareable URL. Fight and attack are separate entries — a distinction that decides real games, and the one the combat explainer spends most of its length on. Threshold has an entry. Casting spells has an entry. So does the Golden Rule, the game's actual first rule, which the Codex's welcome text points to before anything else.
That welcome text also tells you how the publisher intends the thing to be read: not top to bottom, but "like you would Wikipedia or a dictionary." Have a question about a card? Look up the card first. Come to the Codex when the concept behind the card is the problem. There's a Download option and a Changelog in the page's menu, so you can keep a copy offline and see what moved between visits.

The artwork that tops the Codex page — via Curiosa.io
Where it sits in the rules stack
Sorcery's rules authority runs in layers, and the Codex occupies a specific one:
- The Golden Rule. "Use common sense and be cool" — the publisher's phrasing, restated in the November 2025 Judge Program announcement. Kitchen-table disputes are supposed to die here.
- The rulebook. The current PDF is the December 2025 edition, linked from the Codex page itself, with an annotated version that marks exactly what changed. This is the document the publisher wants newcomers to read first — the December update post says it hopes new players "read the rulebook before exploring the Codex." If you're at that stage, the rulebook and the rest of the Start Here resources are the right floor of the building.
- Card pages and FAQs. Every Curiosa card page carries its own official Q&A, and the consolidated FAQ page collects per-card questions for 200+ cards as of June 2026. Most card-specific questions die here.
- The Codex. For when the card page doesn't settle it and the rulebook's treatment is one sentence: the concept-level entry, with the full ruling.
The detail most players miss: the Codex runs ahead of the rulebook. The December 2025 rulebook update describes several of its changes as wording updates "aligned with what's already in the Codex" — Stealth, Pick Up, and Transform all received rulebook text the Codex had been carrying first. Between rulebook editions, the current state of the rules lives in the Codex; the PDF catches up in batches. The rulebook is the foundation. The Codex is the layer that's always current.
A real lookup, start to finish
The December 2025 update hands us a clean worked example, so here's the whole path.
The question. Your opponent has a minion with Stealth, and it's carrying an artifact you'd love to take. You're holding Swap, an Exceptional Magic that reads: "Swap the location of target minion or artifact with another target minion or artifact." Minions and artifacts are two of the four spell types, and Swap doesn't care which it grabs. Can you target the carried artifact and trade it away from its Stealthy carrier?
Step one: the card page. Pull up Swap on Curiosa. Two things are sitting on it. The rules text is live — target, minion, artifact, and location each link straight into their Codex entry. And the page lists five FAQs of its own: the publisher's answers to questions this card has already generated.
Step two: follow the term doing the work. The question hinges on targeting. Stealth's identity, per the Codex definition the keyword hub is built on, is that a Stealth unit can't be targeted by enemy spells or abilities. But Swap isn't targeting the minion — it's targeting the artifact the minion carries. Does the cargo inherit the cover?
Step three: the ruling. It does. Carried artifacts gain the benefits of their carrier's Stealth — the December 2025 rulebook update spells this out and names this exact interaction: such artifacts won't be targetable, "protecting them from effects like Swap." The Codex carried the ruling; the rulebook now agrees with it.
The answer: no Swap. The artifact can't be targeted while its carrier stays Stealthy. Wait for the Stealth to break — per the official card FAQs, it's lost the moment the carrier acts, casting or striking or activating an ability — and the artifact is fair game again.
That's the pattern, and it generalizes: card page → linked term → concept entry. In practice you almost never enter through the front door of curiosa.io/codex; you fall into the Codex from a card page mid-question, which is precisely how the publisher says to use it.
What the Codex is not
Worth being precise about the edges:
- Not a tutorial. The Codex assumes you already know how a turn works — that's the turn structure piece's job, or the rulebook's. Read it like a dictionary, not a course.
- Not the rulebook of record. The Codex's own welcome text sets the order: common sense first, the rulebook "when necessary," and the Codex when you need more depth than either. When you need to cite chapter and verse, the PDF is the citation.
- Not a per-card index. Card-specific questions live on card pages and the FAQ archive. The Codex handles the concepts underneath them.
- Not a judge. It tells you what targeting means; it won't adjudicate the five-card pileup your table just produced.
When to ask a human instead
Some questions are interaction soup — three triggers, a forced move, and a carried relic, all simultaneous. For those, the publisher's own how-to-play page routes you to the community: the official Discord is named there as the place to "clarify rules," and every active server with a working rules channel is cataloged in the directory's Discord Servers section. Asking is normal. The game has years of accumulated edge cases; someone has already hit yours.
Since November 2025 there's also a formal Judge Program. Level 1 requires a perfect score on an open rules-knowledge test — anyone can take it, once per day — and the announcement is explicit that a judge is "far more than a walking Codex." That phrase is doing two jobs: setting the bar for judges, and confirming what the Codex has quietly become — the publisher's own shorthand for total rules knowledge.
Where to go from here
- The Codex — bookmark it next to
/cards; the two pages settle most mid-game questions between them. - Curiosa.io, the Official Sorcery Deckbuilder, Explained — the rest of the platform the Codex lives on.
- Every Sorcery Keyword, Explained — the keyword layer, organized by what each one does rather than alphabetically.
- How Combat Actually Works in Sorcery — fight vs. attack, strike order, intercept: the concepts the Codex defines, assembled into a system.
Sources
- The Codex — Curiosa.io — welcome text, entry structure, Download/Changelog menu — accessed 2026-06-06
- Curiosa card page — Swap — rules text, Codex term links, per-card FAQ count — accessed 2026-06-06
- Curiosa FAQs — per-card Q&A archive, including the Stealth-loss-on-ability ruling — accessed 2026-06-06
- Sorcery: Contested Realm December 2025 Rulebook Update — Codex-alignment wording, Stealth/Swap ruling, rulebook + annotated rulebook links — published 2025-12-19
- Sorcery TCG — How to Play — rulebook / FAQs / Discord routing, card-page FAQ consolidation
- Announcing the Sorcery: Contested Realm Judge Program — Golden Rule phrasing, knowledge-test details, "walking Codex" — published 2025-11-24