How do I extensively, safely mod D&D?

July 18, 2009 10:28 PM

I am attempting to create a new D&D-based RPG, using a lot of non-standard races and rules. Help?

Specifically, I was challenged to create a magic-heavy world that combined elements from Neverwhere, Discworld, and Harry Potter. We will be using v3.5 to start, and half of the crew dislike GURPS.

I'm aware of many D&D-universe flexibilities when it comes to types of campaigns and campaign settings, but I am hoping to modify the rules for certain races, encounters and some mechanics.

While I do have a solid grasp of the playable races from these various universes, the problem is that I am still relatively new to the world of RPG's and D&D in particular, and I know nothing about potential restrictions beyond what's already in the PHB.

Are there any sources available that will help me work out the changes to game and character mechanics without me hopelessly crippling the game? Tips, things to avoid?

posted by neewom to sports, hobbies, & recreation (18 comments total)

Google D20 system.
posted by Ironmouth at 10:44 PM on July 18 [1 favorite]

My advice would be to work with something a little more inherently flexible, like FUDGE or HERO. D&D is mostly good if you want to do D&D - its limits are readily apparent in modding.

But if your comfort zone is d20 stuff, poke around here: http://www.opengamingfoundation.org/srd.html .
posted by mordax at 10:53 PM on July 18

Ironmouth: Did, but it wasn't getting me much of what I was looking for.

mordax: Woo! I am not tied to the idea of using the d20 system, but that is all I've done so far, and I was getting stuck. Thank you for the tips - this really helps!
posted by neewom at 1:37 AM on July 19

If the people you're playing with are friends, (and they are right? Because the amount of work involved in making a coherent custom home-brewed d20 system that won't break when a munchkin gets a hold of it...*shudders*) you ought to be able to get away with fudging things. Do this. Do this extensively. Read any books you haven't read that your players want to use, because at the end of 3.5's life cycle WOTC basically decided to escalate power levels, in a way that really shortchanged some classes. *Endless rant about warlocks and the entire concept of the spell compendium here.* Some of Monte Cooke's stuff might be useful, depending on what manner of systems you are thinking of tweaking/doing away with entirely. The more stuff you make diceless outside of combat the happier you are going to be. Savage Species has rules to make pretty much any monster into a PC with level progression and everything. It also has rules to create your own species. As do about half of the Monster Manuals. If you do use SS ignore the Feral template or bump the CR up a few levels, because the whole fast-healing, bonus strength, and whatever else it adds, (Scent or something) for +1 CR thing is really ugly.
posted by Peztopiary at 3:22 AM on July 19 [1 favorite]

Seconding Mordax. GURPS is another of the very flexible, inherently moddable systems. (And IIRC, they already printed a Discworld game (OOP at this point, though you could check used game shops, Amazon, etc.)

You might check in at RPG.net, if you haven't already. There's a strong thread of people who just love to modify game systems over there. (Just try to have some specific ideas or else you'll get buried under a flood of "Just use [my favorite game]! It's perfect!")
posted by Scattercat at 5:43 AM on July 19

I'm going to recommend Eden Studio's Unisystem--it's less crunchy than D&D, but still pretty simulationist. You can download their game Witchcraft as a free PDF here; I think it could be very easily adapted to a Gaiman-meets-Pratchett-meets-Rowling kind of game world. It'd certainly require a hell of a lot less kitbashing than trying to turn D&D into an entirely new game.
posted by EarBucket at 7:48 AM on July 19

Here's something worth asking - How tied are you to this being realistic (but complex) vs. being pretty laid back (but dirt simple). The problem with most RPG rules systems is that they start with something, they add some stuff here, then some stuff over here and pretty soon a metaphorical walk around the block ends ten miles from where you started.

If I were in your shoes, I'd look for something dead simple and not terribly married to realism and then tweak that. This will make the tweaking easier and, if it's not something your players are familiar with, save you from endless arguments about, "It's not supposed to work like that!" when, since your driving now, yes it is!

I'm not sure what a currently suitable system would be for this endeavor though.
posted by Kid Charlemagne at 8:17 AM on July 19

The 3.0/3.5 D20 rules are complicated, combat-centric, and bound to ancient D&D vernacular. The 4e rules are more streamlined, trading character customization (particularly in the form of the AD&D-descended skill system) for scalability and balance. I know the new license kind of sucks, but consider it anyhow.

Writing up a new RPG is hard. Start by reading good extensions to the D20 model: BESM and Uresia in particular (for a 'point-buy' character-creation system), Mutants & Masterminds, the big Eberron books, Iron Heroes, etc.

Consider a more streamlined storytelling-based system without all the crunchy bits: Mutant City Blues or the new World of Darkness rules, the marvelous (and out-of-print, alas) Dying Earth game, etc. Think of Risus and FUDGE as models for starting small. Look too at Savage Worlds, a superbly playable pulp-action game.
posted by waxbanks at 8:38 AM on July 19

True20 might be what you're looking for. It's a simpler d20 mod meant for more cinematic action. It's fairly good at magic heavy games, since it doesn't have Vancian magic. It's close enough to D&D that converting material over it is fairly simple.
posted by Pseudoephedrine at 8:40 AM on July 19

Seconding Kid Charlemagne, a lot. I'd consider looking at some indie RPGs as a baseline for this kind of thing because of the simplicity you want, but I'd have to know more about your group to offer decent advice.

For a commercially available but out of print system you might use as a baseline, I might also look at Everway. I've been co-GMing an Amber-based PBEM using Everway as a basis for about eight years now, so I have a fair bit of experience kitbashing with it. I've also considered it for Potterverse. Feel free to MeMail me with questions.
posted by immlass at 8:46 AM on July 19

I, personally, would go with either GURPS or Basic Role Playing (BRP, the Chaosium system). Harry Potter et al seem primarily skill-based systems; what you know defines what you can do. Also, they deal in the realistic consequences of actual magic, which, to my mind, defines what Potter, Discworld and Neverwhere are really all about.

I'll recommend BRP, since the transition from a d20 system to a a D100 system seems easy-peasy. (Although, do consider Discworld's narrative-based logic; if a player should be able to do something because it makes a better story, then he or she should have a better-than-even chance to do it.)
posted by SPrintF at 10:59 AM on July 19

I know this probably won't help you much, but just thought I'd add a few things that Gary Gygax (creator of DnD) taught. There aren't any rules to the games, there are just guidelines and the only reason to roll dice is we like the way it sounds. So basically, you aren't necessarily restricted more by one system or another. Good luck!
posted by Deflagro at 11:32 AM on July 19

* Don't Be A Monotheistic GM: Enlist the players' help in building the world. Allow them the latitude to make up things they want to interact with, engage them in building culture and legend, let them go in directions you didn't intend.

* Consider GM's "trading 20s": let one person run the game for a more-or-less self-contained story arc, then swap out. If you award a GM's character roughly the same experience as the players get while he or she is running, everyone keeps up and can play with each other's direction for the overall campaign world.

* Ridiculous elaborate puns and hidden references the players may never get: I've had great fun building giant parts of worlds and campaigns around bad Homer jokes and Led Zeppellin songs. They can provide a framework to work from, inspiration for "blank spots", and joyous groans if someone notices. Note - I don't mean campaigns set explicitly in that context, just use it as a hidden structure - like Joyce with Ulysses. Yes I think you can think about well done roleplaying in literary terms and defy anyone to disagree who actually knows anything about either.

* As far as rules: we have a roughly year-long cycle about the importance of rules. Some games we barely crack the books and just interpret dice rolls as we wish. Sometimes we get super technical. It's fun to switch around, depending on the type of story and characters involved. Everyone is right upthread about not overdoing the rules, and light systems are fun. That said, d20 is a nice system, and after years of spending time arguing rules, I find it's valuable to just do what the books say and spend time on the important stuff. So I'd find a system that does most of what you want, and not mod it too much - spend that time on story. Unless you really want uber-technical combar rules - in which case, for a fantasy game, D&D 4.0 is very well done. They nailed the fantasy melee niche, if that's what you want.
posted by freebird at 12:22 PM on July 19

Now that I think about it -

I, personally, would go with either GURPS or Basic Role Playing (BRP, the Chaosium system). Harry Potter et al seem primarily skill-based systems; what you know defines what you can do. Also, they deal in the realistic consequences of actual magic, which, to my mind, defines what Potter, Discworld and Neverwhere are really all about.

Another helpful design example: Mutant City Blues!! It's a story-driven skills-based investigation game from Robin Laws: NYPD Blue + X-Men, with a superb mutant-powers tree (called the Quade Diagram), minimalist mechanics, strong investigative flavour (like the HP books, not so much Discworld)...just a lovely game. But it's specifically designed for investigative roleplaying, not high-fantasy mucking about.

Have you considered GURPS Ultra-Lite? It's like 20 pages long.

I'll reiterate the stylishness and appropriateness of BESM, by the way, and Mutants & Masterminds: scalable D20 stuff with interesting point-buy character creation. 4e is cleaner but those are mighty flexible games.
posted by waxbanks at 1:08 PM on July 19

Okay, I'm about to go best-answer-crazy, sorry.

I'm glad I remained open-minded about the mechanics and what I should and shouldn't be considering, because from the tips, I have a lot of different options with the game mechanics, what the players themselves will actually like, and what sort of creatures I can come up with.

Two of the players dislike GURPS, but I'm inclined to borrow from it, especially as there are already GURPS-based worlds available for at least two of those I listed (Discworld and Neverwhere), but FUDGE seems to be a great option as well.

Given the complexities I could face, I'm really leaning more and more towards keeping it simple. If you guys are interested in the outcome, I'll let you know what I end up going for.
The difficulty for me in all of this is that a) I have never done this before and I'm an RPG newb; b) four out of eight of us are RPG veterans with many different systems under their belt, and I could easily make this too crappy for them.
For now, given the suggestions (in no particular order):

1. Keep it as simple as I can
2. Give the players something familiar (rules-wise and character-wise)
3. Make the players laugh, even if they don't get the puns
4. Don't tie the game too much into the realities of any particular world, because that could easily get complicated
5. Let the players take turns running the game in whatever arcs seem fun
6. Actively enlist the players in creating the game itself
7. Borrow a lot of books from their stack of indie-games. Read, read, read, then lie.
8. If I take from D&D, consider getting out of 3.5 and move to 4
9. Consider the lessons learned from existing modded and original games and learn from them
10. Beg the veterans for help. I know I already said that, but this bears repeating.

Thank you again for the amazing tips, especially what I should try to avoid and where to look for inspiration. My biggest goal in this is to create something workable and fun for the players without making it too far from what the players already know. It seemed to me that I could easily screw this up for them if I didn't get help, and I'm extremely grateful for the tips you've provided.
posted by neewom at 1:30 PM on July 19

Ask this question at the Forge. It's a forum for people developing pen and paper RPGs. You'll receive some thoughtful feedback from established designers as well as insightful questions that prompt you to dig deeper into your process.
posted by Orchestra at 1:47 PM on July 19

Two super simple rules systems I haven't seen mentioned yet are PDQ and Risus ...these seem really fun: just enough mechanics to feel like rolls matter; light enough to avoid rules fights and descent into esoterica. Both are close to the "one-page" ideal, and very narrative in focus. I chose PDQ for a rule-light Play-by-Post project, but Risus looked really cool and I can't remember why I made the choice I did :)
posted by freebird at 3:54 PM on July 19

One other thing to consider is the Rule of Cool. Allow characters to do stuff even if you don't have a specific rule for it. Or even if it breaks the rules as long as your players aren't power gaming gits. One of the reasons I like the first edition of AD&D is so many of the rules were game breaking if pushed to the limit but totally epic if used in moderation.
posted by Mitheral at 7:18 PM on July 19