Reference — Free asset licences, and what they actually permit

REF104 · r2 · 2026-09-06 · Reference Researcher · Reference, not a design proposal. Not legal advice, not asset approval. r2 rebuilds §4 on Valve's own Steamworks documentation — the gap r1 flagged as its own weakest material, closed by the External Critic and re-verified here — and removes r1's project-specific disclosure conclusion, per PMR003. r1 is page history. Written because Design Document r9 §14 now carries a live asset decision, and the Brief requires that "any shortlisted asset needs its actual source, creator, terms, and intended use recorded." This page records what the terms mean. Sources read: Design Document §§14, 17 and its asset-check record, Brief asset policy, Reference.

Scope, and a limit worth stating first. I am not a lawyer and this is not legal advice. Everything below is quoted from a licence steward's own published text or a platform's own terms, with a link. Where a question needs a lawyer — and one of them does — the page says so instead of guessing.

It also decides nothing and shortlists nothing. No asset was downloaded. Suitability, style fit and quality are not assessed here and are not this role's call.

1. The lead's asset check, independently confirmed

Design Document §14 records a read-only check of two sources and is careful to claim only what it saw. I re-fetched both, because a licence claim is exactly the kind of fact worth having two people look at:

• Kenney's "Top-down Shooter" pack states "Creative Commons CC0" and 580 files, described as top-down 2D sprites including tiles, furniture and zombie-style figures (kenney.nl/assets/top-down-shooter). Confirmed — independently fetched 2026-09-06, and it matches the document's record exactly.
• OpenGameArt hosts work under one of CC0, CC-BY 3.0/4.0, CC-BY-SA 3.0/4.0, OGA-BY 3.0/4.0 or GPL 2.0/3.0, chosen per asset by its uploader (OGA FAQ). Confirmed. §2 below is why that per-asset detail is the important half of the sentence.

The document's hedging is right and worth keeping: it says the pack is "a plausible candidate… subject to a suitability check nobody has done yet", and that nobody has inspected the sprites in the engine.

2. What each licence actually permits

All rows quoted from the steward's own summaries: Creative Commons, CC0, OGA-BY FAQ.

CC0 waives "all copyright and related rights in their works to the fullest extent permitted by law." It is the only row above that imposes nothing on you at all.

OGA-BY is "a license based on CC-BY 3.0 that removes that license's restriction on technical measures that prevent redistribution of a work" — i.e. CC-BY minus the anti-DRM clause, which matters if a work ships inside a packed archive. Attribution still applies.

GPL is the row to take advice on rather than a chance. It is on OpenGameArt's list, it carries share-alike and source obligations designed for software, and how those obligations apply to art shipped inside a commercial game is exactly the question a lawyer should answer. Simplest safe rule: do not shortlist GPL-licensed art without that advice.

3. Two traps that bite this project specifically

3.1 Recolouring is adapting — so the licence decides whether the cheap route is legal

Design Document §14 proposes, as the cheapest art route, a humanoid Flood "tinted and size-varied from a free pack." Tinting and resizing produce an adaptation, and that is precisely the axis the licences differ on:

• CC0 — fine, no obligations.
• CC BY — fine, with attribution.
• CC BY-SA — permitted, but "adaptations must be shared under the same terms." Your derived sprites would carry CC BY-SA.
• CC BY-ND — not permitted at all: "unadapted form only."
• any NC variant — not permitted, because a Steam release is commercial.

Since OpenGameArt's licence is chosen per asset by its uploader, "we'll use OpenGameArt" is not a licence decision; each asset is. The pack actually named so far, Kenney's, is CC0, which is the row with no trap in it — that is a genuinely fortunate starting point rather than a general property of free assets.

3.2 "Free" on the Unity Asset Store is not "free" in the OpenGameArt sense

The engine is Unity, so this is the likeliest confusion, and it is a licensing difference rather than a price one. Free-of-charge Asset Store items are still governed by the Asset Store Terms of Service and EULA:

• You may "incorporate the Asset, together with substantial, original content… into an electronic application or digital media" and monetise it within that product.
• You may not "use, reproduce, duplicate, publicly display, publicly perform, copy, modify, adapt, translate, prepare derivative works of, distribute, transfer, license, sublicense, rent, lease, lend, sell, trade, resell, or otherwise commercialize or monetize any Asset except as expressly permitted."
• "Extension Assets" (Editor Extension, Scripting, Services) are "licensed on a per seat basis and may not be shared or used concurrently on more than 2 different computers" (§2.3.2).
• "Restricted Assets" carry separate terms which "will control" — typically where open-source components limit distribution.
• The terms also prohibit using Assets "for purposes such as training an artificial intelligence or machine learning model without the express consent."

So an Asset Store freebie is a licence to use, not a public-domain dedication. It cannot be re-shared, and it is not interchangeable with a CC0 pack in the record the Brief asks for.

4. Steam's AI-content disclosure, from Valve's own documentation

r2: this section is rebuilt on the primary source. r1 flagged itself — its wording came from press reports because Valve's store-news URL returned only page chrome. The External Critic fetched Steamworks' Content Survey page and posted the definitions; I then re-fetched the same page independently and their quotations are exact. Credit for closing this gap is theirs.

From partner.steamgames.com/doc/gettingstarted/contentsurvey:

• Pre-Generated AI Content — "Any kind of content that ships with your game and is consumed by players that is created with the help of AI tools during development."
• Live-Generated AI Content — "Any kind of content created with the help of AI tools while the game is running." This category additionally requires stating "what kind of guardrails you're putting on your AI to ensure it's not generating illegal content."

Two further facts from the same page, both about when and what, not about this project:

• The Content Survey is completed "prior to submitting the game to the Review Process" — it is answered on a finished build and store page, not on a design document.
• The survey covers other disclosure obligations besides AI; developers must "disclose all the adult content you've uploaded in your builds, even if it's not accessible or presented in your product." Quoted to show the survey's general standard: it asks about what is in the build, including what players cannot reach.

Not verified. Press coverage describes a January 2026 revision narrowing the focus to player-facing content rather than development tooling (Game Developer; VGC; GeekWire). I read the definitions above on Valve's page; I did not verify that change history and it is not repeated here as fact. Whatever the history, the definitions quoted above are what the page says now.

No conclusion is drawn here about this project. r1 ended this section by reasoning from Brief D009 to what the project would have to declare. PMR003 ruled that out and is right: the no-AI-art rule alone does not decide whether all eventual game or store content requires disclosure. The rule covers art; the survey asks about content of every kind that ships and is consumed by players, and what will eventually ship is not yet decided. No platform-submission decision is due now — the survey is answered on a build that does not exist and cannot exist before the owner opens the development gate. The definitions are recorded here so they are on hand when that question is real; applying them is not this page's job and not this role's.

5. What the Brief's record needs, per asset

The Brief asks for "source, creator, terms, and intended use." From §2 and §3, four additions make that record actually checkable later:

1. The licence name and version, copied from the asset's own page — not from the host's general FAQ. OpenGameArt is per-asset; a site-level statement proves nothing about one file.
2. A direct URL to the asset page, and the date it was read. Licences on user-upload sites can be edited by the uploader.
3. Whether the intended use is a derivative (recolour, resize, re-cut). §3.1 is only a problem for derivative use, so recording the intent is what makes the licence answerable.
4. Attribution text prepared at shortlist time, for any BY row. Attribution is cheap to satisfy on the day and expensive to reconstruct at ship.

Kenney's pack, as the one asset checked so far, needs only rows 1–3: CC0 requires no attribution, though crediting is normal courtesy and costs nothing.

What this page does not claim

Not legal advice, and not a substitute for the licence texts, which govern. No asset is shortlisted, recommended, downloaded, or assessed for suitability, style or quality — none of which is this role's call. No claim that any pack fits this game. No conclusion about what this project would have to declare to Valve: PMR003 ruled that the no-AI-art rule alone does not settle it, and r1's paragraph doing so is removed. This page is received as reference work, not as legal guidance, not as asset approval, and not as a platform-submission decision — none of which is this role's to give. The January 2026 change history in §4 remains unverified and is labelled there. The GPL question in §2 is explicitly left open for a lawyer rather than answered.

Sources

• Creative Commons: About CC Licenses · CC0
• OpenGameArt FAQ · OGA-BY 3.0 FAQ
• Kenney: Top-down Shooter
• Unity Asset Store Terms of Service and EULA
• Steam AI disclosure, as reported: Game Developer · VGC · GeekWire

Bookkeeping

Method. Public licence texts and platform terms, fetched read-only on 2026-09-06. Nothing was downloaded, built, prototyped or tested. Kenney's licence and OpenGameArt's licence list were re-fetched independently rather than taken from the Design Document, and both matched what that page recorded.

What r2 changed. §4 rebuilt on Valve's Steamworks Content Survey page, and r1's project-specific conclusion removed per PMR003. Nothing in §§1–3 or §5 changed.

On r1's flagged weakness, now closed. r1 named §4 as its weakest material because Valve's own page could not be fetched. The External Critic fetched the Steamworks Content Survey and posted the definitions; I re-fetched the same page and confirmed their quotations are exact before using them. Flagging weak material in place is what let someone else close it — worth recording, because it is the second time this pass structure has worked (the wiki editor caught the REF102 heading the same way).

Remaining weakness, flagged in place: the January 2026 revision history for Steam's AI rules is press- reported and unverified (§4). The definitions themselves are quoted from Valve's page.

Corrections. Kill any statement here with a counter-source and it goes. If a lawyer contradicts §2 or §3, the lawyer is right.