How can I publish my alternate sphere rules for Mage?

Storyteller's Vault should be your next stop.

The Dark Pack license is for material that's not meant to be sold or distributed for gain. If what you want is to publish your material, the information and licensing you'll need is found on the Storyteller's Vault. The STV license lets you use World of Darkness trademarks and sell on their creator content site in exchange for a cut of the money. The material you've shown would be in line with what's available there. Here's a place to get started.

Follow their guidance and ask on their Creators Discord or social media

The Dark Pack Agreement only allows you to share if you are not making money from your content

You can create and share the following non-monetized and non-commercial content:

So if by "publish" you mean to charge for your alternate rule (for example on a site like DriveThruRPG), that is very clearly not allowed under this license.

If by "publish" you just mean to make your content freely available, its less clear. The above intro is followed by a bullet list of things that are allowed, and that list does not include alternate rules systems. (The closest is a reference to another agreement about game mods, but as far as I can tell, that one is about computer games that you access through Paradox's services).

The agreement then says

If the kind of content you want to make and share isn’t listed above please feel free to contact us and ask about it through our social media or Creators Discord.

So I’d recommend you do that.

Let's look at a short glance who owns the game. Since about 15th October 2015, that's Paradox Interactive, owning White Wolf Publishing, who licensed some of the RPG line to Renegade (the original 5th editions of Vampire, Hunter, and Werewolf) and Onyx Path Productions (20th Anniversary Editions).

Paradox has deemed it proper to offer two licenses to the general public for 3rd Party products on the main line:

Dark Pack Agrement

The run of the mill fan content license for non-commercial, freely published products is the Dark Pack Agreement. The primary goal is to enable fans to exchange their fun items with one another, free of charge, without infringing on the rights of Paradox and its subsidiaries.

You don’t need to ask for our permission before creating and sharing most types of content as long as it is non-commercial. Anyone can stream an actual play of Vampire: The Masquerade, make and share cosplays and fan art, run a World of Darkness LARP, or even make and share a short fan film on YouTube, without asking us first if it’s okay–again, if the content is non-commercial.

• Your use of World of Darkness IP is strictly for non-commercial purposes only. For example, you may not offer goods or services for sale in connection with your use of the World of Darkness IP.

But there's some slight limelight in the FAQ: you may get donations to keep the thing running, but you might need to inquire for another license if you want to make a profit, as the FAQ shows with LARP examples:

Q: Can I ask for donations to help defray the cost of running my LARP event?

A: Yes. We recognize that it’s often necessary to pay for a safe and comfortable LARP venue, and that asking for donations from your players helps cover those costs. This will include the vast majority of casual LARPs that are not organized for commercial purposes. We in no way want to discourage your LARPing!

Q: Can I charge fees for LARP membership in my LARP organization, or fees for attending my LARP event, that are in excess of covering my time and materials?

A: Yes, but if your LARP is a commercial business and its fees generate net revenue in excess of time and materials, we may require you to have an additional license. This isn’t to make life more difficult for LARP organizers or players, but to ensure that our intellectual property is protected in the way laws require it. We recognize that this may seem vague, but we are actively working on a more specific and detailed policy with input from LARP organizers. Until we can share that we ask for your patience and that you contact us through our social media (Twitter DM or Facebook message) if you are in any way uncertain about your LARP.

Storyteller's Vault

But fret not, Paradox brought us an alternate license that explicitly allows you to sell stuff! Well, not any stuff, but rules. The Storyteller's Vault is a Drivethrurpg imprint for WoD, CoD and Exalted products - all of which are White-Wolf products. Selling there follows different rules and guidelines from Dark Pack, and it's explicitly made to monetize fan content, with a cut going to the STV and Paradox Interactive. Yes, you pay a licensing fee, but you can earn a few bucks.

May I have AI content?

AI-generated content on any DTRPG site or imprint is limited: primarily AI-generated text was banned in July 2023, and any AI-generated art needs to be disclosed by settings (from Storyteller FAQ):

With that in mind, we will start enforcing our existing policy in response to AI art usage starting from early next year. To ensure all creators will have time to react to this clarification and swap their AI-generated assets, we will begin enforcing this rule on February 12th 2024.

After this date, other creators can report suspected AI art usage to Storytellers Vault by using the ‘Report this Title’ button.

That points to the rules set on the main site, where each program retittates the same rules again and again, at times with slightly different wording (emphasis mine):

AI-Generated Content Policy

Update March 24th, 2023: The following policy applies to DriveThru Marketplaces, including Community Content Programs and Supported Marketplaces. DriveThruRPG defines “AI-Generated art” as images created through the use of artificial intelligence algorithms and techniques trained on pre-existing data sets. (Examples: Midjourney, Artbreeder).

• At this time, DriveThru Marketplaces require partners to set their own AI-generated artwork policies on all game rulebook and adventure products. If AI tools were used to generate any of the content in your title, you are required to indicate this using the Creation Method filter.
• At this time, DriveThru Marketplaces do not accept any standalone artwork products that utilize AI-generated tools to make content.

Update July 19th, 2023: While we value innovation, starting on July 31st 2023, Roll20 and DriveThru Marketplaces will not accept commercial content primarily written by AI language generators. We acknowledge enforcement challenges, and trust in the goodwill of our partners to offer customers unique works based primarily on human creativity.

As of May 29, 2025 DriveThru Marketplaces are including "AI prompt" products in the types of titles not accepted to be published.

Note: Our Partner Relations team reserves the right to add filters and remove filters if a title is not properly marked. Titles that do not comply are subject to removal from the marketplace. Repeat offenders may have their publishing permissions revoked.

A full statement of intent regarding our policy update can be found in our AI Generated Artwork Policy Updates forum post. Community content program policies are dictated by the publisher that owns it.

For a list of artwork resources you can use in your products, visit our Artwork Resources for Your Products article.

Creation Method Filter If your Game, Rulebook or Adventure product contains AI-generated content, you are required to indicate this using the Creation Method filter. In order to enable this filter, find the Category Assignments section under Filters when you Set Up a New Title or Edit a Title Listing. Under Format near the bottom of the filters list, find the box labeled Creation Method. Click the black triangle and it'll expand the dropdown list, where you can then select AI-Generated.

Third way: License Negotiations

If you really think that you have something different and want to publish elsewhere than under the DPA or in the STV, you need to contact Paradox Interactive. That requires the proper address to start negotiations for a different license, and that's the most tricky part. One way you might find who to write to might be to inquire via the Public Relations Teams (allegedly they have a Twitter and Facebook page and answer to DMs), or via the Paradox Creator Discord (where you also can get clarification on the DPA).