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Jonathan Tweet: My Life with the Open Gaming License

In 1978 at age 12, I bought my second roleplaying game, Metamorphosis Alpha (MA) by Jim Ward. That’s the day I became a fan of the Open Gaming License and the d20 logo. Or at least I would have been a fan if someone had gone back in time and told me about them.

The rules in MA described a different reality from those of Dungeons & Dragons, and I was disappointed. I already knew how many Hit Dice wolves, humans, and other creatures had; how combat worked; how experience and levels worked; and more. MA ignored all that and presented a different system. If it had been an improved version, I would have been OK with it, but it was just a different way of doing things, and it didn’t even have an experience system. I felt as though TSR had betrayed my trust. Even so, we played a lot of MA, at least until Gamma World released and we bought that game. It came in a box and a had a map of a war-devastated North America, so we were sold.

In 1979, I switched largely to RuneQuest from Chaosium. It had a single dice-rolling mechanic that it used for everything: magic, skills, and combat. The system was designed from the ground up to be rational. Within a few years, the publisher used variants of the same system for their other roleplaying games, notably Call of Cthulhu. It made sense to me that if a publisher’s RPG rules were good then they’d want to use those rules for all their RPGs.

Meanwhile, GURPS from Steve Jackson Games showed how much mileage a publisher can get out of a single RPG system.

After I started doing professional game designer, Mark Rein•Hagen and I dreamed up simple, universal dice-pool system that we thought could apply to any setting. He ended up developing some of those ideas into the core mechanic for Vampire: The Masquerade, which then served several other RPGs. I derived a different dice-pool system and used mine for Over the Edge (Atlas Games, 1992).

My interest in universal systems rose again in 1997, when Wizards of the Coast purchased Dungeons & Dragons. Along with D&D, Wizards acquired Alternity, the as-yet-unpublished science fiction game that TSR had been working on. As with MA, Alternity was designed with a novel rules system, which made it harder for RPG fans to pick it up and play. Wizards not only released the game but then followed up with a series of settings for the same universal mechanics. The idea of using one rules system for multiple settings makes sense, but in this case it was a rule system that no one knew and that was incompatible with the system everyone did know: D&D. Predictably, Alternity never really got off the ground despite the large number of support products released for it.

I was working at Wizards when they acquired D&D, and my plan was just the opposite. I got approval to do a standalone RPG using D&D-style rules, and it was going to be Gamma World. Finally I was going to do mutants and lasers with D&D-style rules, just like I wanted from MA in 1978. My new take on Gamma World was bound to be a strange product with no logical place in the D&D line, but it was part of the Odyssey series of D&D settings, and those were all strange products with no logical place in the game line.

The plans to do D&D-style Gamma World as an Odyssey product came to an end when Ryan Dancey took over as the brand manager for roleplaying games. His first priority was to unify the AD&D audience, which had been fractured by the release of multiple, incompatible settings. While he was trying to bring AD&D players back to a single line of products, the last thing he wanted was a post-apocalyptic version of AD&D. My dream of lasers and mutants with D&D rules was denied.

Ryan had plans of his own, and they were more ambitious than mine. He released D&D 3rd Ed with an Open Gaming License and the d20 license, which let other publishers publish D&D supplements—provided the serial numbers were filed off. In 2000 when 3rd Ed released, the exhibitor hall at Gen Con was full of publishers trying to lure players away from D&D. A year later, they had gotten on the bandwagon, and publishers all across the exhibit hall were encouraging players to play more D&D and buy their d20/OGL products. The OGL was a tremendous success. Both Wizards and other publishers released new RPGs using D&D rules, just like I had hoped 20 years earlier.

The other half of the Third Edition project was getting the D&D rules in shape. As the lead designer, I took a lot of inspiration from RuneQuest, and we succeeded at developing a game system that was rational to port into other settings, again including Call of Cthulhu.

Some people in the RPG department, however, never liked the OGL, and when 4th Edition rolled around, the license that came with it was unfriendly. Paizo, which have been supporting D&D like mad through the OGL, switched to being a competitor with Pathfinder. Fourth Edition D&D had a lot of issues, and one of them was lack of 3rd-party support.

With 5th Edition D&D, the folks who opposed the OGL are gone. In fact, the fellow who runs D&D design, Mike Mearls, did a big, cool d20 book for Monte Cook, Iron Heroes (2005). Publishers are having a great time supporting the new version of D&D with products labeled “5E”.

A best friend of mine is Rob Heinsoo, the lead designer on 4E. He and I created a d20-style RPG called 13th Age (2013). It has a lot of same rules and elements as D&D, but it’s streamlined to create more dynamic battles and more player-driven story. Our game, in turn, is supported by people who use our open gaming license to publish their own compatible material.

A lesser known game of mine was a d20 version of Gamma World. It was called Omega World, and it released in 2002 as part of Polyhedron Magazine. It features weird mutants, dangerous technology, murderous monsters, and a high body count. My 12-year old self would be happy to hear about it.
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Jonathan Tweet



Well, that was fun
Staff member
So, yes, I wonder if the centralization of the DM's Guild has led to a bit more awareness of what's out there and less overlap. And, I wonder if we're seeing a lot fewer 5e offshoot games than we did back in, say, 2002, because of the DM's Guild.

Sorry if this is kinda vague. I'm spitballing here.
The DMsG is another massive glut, but it’s all electronic and not choking up distrubutors and discount bins. Plus WotC gets half the money and keeps the rights, and you can’t make your own settings.


The DMsG is another massive glut, but it’s all electronic and not choking up distrubutors and discount bins. Plus WotC gets half the money and keeps the rights, and you can’t make your own settings.
"it's all electronic" doesn't help when visibility is rubbish. Steam right now has the exact same problem, albeit to a much larger degree. Many indie developers would rather release for the Switch than on Steam purely because of just how many games are on the platform, and many of them are just plain garbage. I don't think we're likely to get to the point of Steam with the DMs Guild, just because of how popular video games are compared to D&D, but "it's all electronic" doesn't magically make the problem go away.


It doesn't help with poor discoverability, per se. Unless you really know what you're looking for, the DMs Guild site is pretty rubbish for discovery. By "discovery", here, I mean "show me things like what I already liked". This is subtly different from "show me things that people who bought this item also bought", in that I could just as easily buy, for example, Raging Swan Press's 20 Things Volume IV and also the 3.5 Monster Manual (and have done exactly that). But these things are entirely unrelated to one another.


Now I wonder about d20 Modern 2.0. I am not talking about a corebook and ten sourcebooks, but a very important project for WotC because it may be the key for Hasbro's franchises, and maybe other companies. You could be create a RPG of Fornite, G.I.Joe or Action Man, but if we want a d20 version of Transformers or Power Rangers then the things changes. Worse if WotC could get the rights for some famous superheroes franchise.

But d20 Modern could allow some changes of the sacred cows, for example new abilities scores (Courage, Astuteness, Grace(=karma/luck/fate) and Technique (crafting, playing music, dance, martial arts and martial maneuvers..) and some third companies would use it for adaptations of their own franchises.

Jonathan Tweet

[TSR] was a premier publisher of games, period, and not limited to just one rule system or genre.
Maybe there would have been a way to make a broad range of games work, but the market logic of intellectual properties and brands makes it easier to be profitable when a corporation piles onto the IPs and brands that are already the most successful. As a creator, I love the idea of a range of games. That's not what I would recommend to a publisher unless they had a remarkable plan for making it work.

Jonathan Tweet

@Jonathan Tweet - what are your feelings about how the OGL has somewhat morphed into the DM's Guild? While I realize that no one is restricted from using the OGL to reach gamers in other ways, it seems that the DM's Guild is the main portal. What do you think about that?
I sort of love it, but I haven't looked into it well enough to have a professional opinion. To me, it feels like a great way for a corporation to acknowledge fan content. Roleplaying games have been worth spending my life on because they encourage the creativity of regular people.

Jonathan Tweet

Omega World remains one of my favorite games. I have a subscription print copy, a retail print copy, and the pdf. I would run or play it at the drop of a hat.
Thanks for that. Omega World has a special place in my heart, and pound-for-pound it might be my best RPG work ever.

Jonathan Tweet

The fantastic advantage of OGL is that games can live on and evolve further.

3.5E -> Pathfinder -> Pathfinder 2E
13th Age -> 13th Age Glorantha
13th Age -> King of Dungeons

I've had an incredible run of 13th Age over a span of several years, and I will probably run it again (though probably using King of Dungeons).

Thank you.

As for 4E, well, the way it was introduced into the world led to division among people. Honestly, I tried to like the system, but when I learned about its lack of OGL support, I gave up on this.
You're welcome, and I'm super happy with how the OGL has helped RPG systems develop, just as you say. Internally, when we learned that 4E wasn't going to have strong OGL support, many of us were also mightily disheartened. 4E was, seemingly, built as the anti-3E.

Jonathan Tweet

I started playing tabletop (as opposed to D&D CRPGs like NWN) at the time when 4th edition was new. When I learned that it didn't support the OGL, I had a sinking feeling in the pit of my stomach, a fear, a dread, that would later come to be confirmed in ways that I couldn't--wouldn't--even imagine. 4E killed the game I loved in so many ways, and it's not recovered since. 5e's backpedalling just doesn't provide the rules my group needs (it backpedalled to OD&D rather than 3.x), so we'll be sticking with 3.x (and thus the OGL) for the foreseeable future. Long live the OGL!
Indeed. Ryan Dancey deserves a medal or something.


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