Question: how much extra effort would it really take to write modules supporting multiple systems?

[Blue]

However, there are lots of "strange" references that make no sense in a Pathfinder context. (These are all from memory, so apologies if I get some of the details wrong.) Half Elven grooming rituals? Making a point of mentioning that a wizard wields a gold orb. Some monsters changing tactics when they get "bloodied". Someone helping out his friends with "a series of leaps and jumps" but not having any ranks in Acrobatics? I think there were other references to rituals as well. None of this impacts on my ability to run the adventure - but it might have, and gives me something additional to think about, which as a Pathfinder GM running a complex adventure, that's not something I need.

(And it could have impacted on the adventure - I read a 5th edition adventure where the body of a shark-like humanoid is found; later these turn out to be sahuagin, which have an affinity for sharks but don't much look like them. Turns out this is a conversion of a Pathfinder adventure featuring Adaro, which are shark-human hybrids but don't appear in D&D.)

Agree with everything you said. I just needed to support your point that it's not just encounter design, but even lore, culture, and existing of certain foes can be challenging to convert between systems. Making the a multi-system adventure really needs to keep to the least common denominator, which might be quite repetitive or overdone.

 

[Calthropstu]

Agree with everything you said. I just needed to support your point that it's not just encounter design, but even lore, culture, and existing of certain foes can be challenging to convert between systems. Making the a multi-system adventure really needs to keep to the least common denominator, which might be quite repetitive or overdone.

I agree as well. Hdnce why I am thinking, more so at this point, that a publication website catering to adventures able to support multiple systems can be developed more easily.

Ultimately, "I have a story you can interact with" is the purest essence of rpgs. I see no reason a story must be restricted to a particilar system. A publication tool allowing support of multi system publishing seems like a great way to support systems both old and new.

I am beginning the process of hammering out the details of how this would work. I have experience programming the assembly of pdf files, so I am fairly certain I can do this.
I think the best way to do this is place the statblocks in its own section and have encounters refer to the block. Much easier to program that way.
wanders off to do some thinking

 

[5atbu]

It's a perfectly interesting idea that many have done. Oddly.. they never sell as well.
Seems that by doing it you dilute the brand identification.

Given that you don't need to print in advance on Drivethrurpg, it seems a better marketing choice to produce variants per system.

 

[Dausuul]

The differences between editions of D&D go far deeper than whether an ogre is CR 2 or CR 3.

When 4E was released, the first adventures Wizards put out (e.g., Keep on the Shadowfell) were absolutely godawful. They were designed like adventures in previous editions, with lots of small encounters spaced out through the dungeon. And if you're playing BD&D, that model works great. You kick down the door, whack a couple orcs, and in five minutes of real time you're ready to loot the room and move on.

But 4E is tailored for big, elaborate set-piece battles. There's no such thing as a five-minute encounter in 4E. Each initiative roll means 30 minutes of combat, minimum--even if it's a pushover and the party's victory is never in doubt. So all these little "attrition encounters" became a huge, pointless time sink; and thanks to 4E's encounter-centric resource model, they also didn't cause attrition. Nobody's going to burn a daily power on an Easy fight.

To sum up: KotS was exactly what would happen if you took a BD&D adventure and tried to do what you propose. And it was excruciating.

For another example, teleportation can bypass loads of obstacles and has a huge impact on adventure design. In older editions, low-level teleportation is pretty much nonexistent, but in 4E and 5E it's common (e.g., misty step or an eladrin's Fey Step power). On the other hand, long-range teleportation comes online much earlier in previous editions.

And I can only imagine how much bigger the gap would be with a whole different system. I would not try this unless you were working with systems that were deliberately designed to be compatible (e.g., 1E/2E, or 3E/Pathfinder).

 

[Eltab]

Probably already mentioned:
The big problem I see is the pagecount eaten up designing every important NPC twice and printing those stat blocks.

As an extreme example, Laeral Silverhand is fully statted out in the D&D 3e sourcebook Waterdeep: City of Splendors. She is two full pages long. Now repeat for D&D 5e (because she has a cameo in Dragon Heist) and some other rules system.

 

[Umbran]

The downside of that approach is having to wade though all that material for every room when it's surplus to requirements. I dont think its very user freindly. A less aggravating approach woupd probably be to include the additional ruleset material in a series of appendices.

I think this makes a central issue apparent. Those appendices are extra design, playtesting, and pagecount costs. Each of your customers likely only uses your work with one ruleset - so, broadly, your product is likely overpriced, as compared to a single-ruleset product.

The question is, will the extra ruleset support offset the loss of sales due to higher price? I don't think we can assume it will, or won't.