This re-purposed quote, variously attributed to Picasso, Lennon and Eliot, holds as true for campaigns as it does for art. There are plenty of good ideas out there and no good reason not to steal them outright – just make sure that if you publish, you have got the OGL to back you up.
For my Wilderlands campaign I stole:
Encumbrance and Movement from James Raggi’s Legend of the Flame Princess, who revised significantly (and brilliantly) the rules in Dan Proctor’s Labyrinth Lord, who OGLed them based on the Moldvay/Cook Basic and Expert Rules, which were a revision of J. Eric Holmes D&D basic rulebook, which were adapted from Gygax and Arneson’s Original D&D. (Whew. From here on in I’ll just list my primary source.)
I stole these rules because they were the easiest implementation of encumbrance and movement, better than the Swords & Wizardry rules, if only because they required less math. Raggi also implemented the rules on the character sheet in such a manner as to make tracking encumbrance easier. I stole most of the design of his back of the character sheet for my sheet as well.
The only easier system would be to use item cards, and allow an amount of cards based on strength, which I may still implement if my players don’t start tracking encumbrance better.
I also lifted Raggi’s treatment of Skills from LotFP, which is based solidly on the original d6 rolls that players could attempt in previous versions. These include (from OD&D) noticing secret doors, finding food and water in the wilderness, avoiding traps, sneaking, and surprise. Raggi renames these and formalizes them somewhat; I do the same, but have a slightly different list.
Everybody has at least a one in six chance to perform these tasks, while some start out with a greater chance, while non-human classes (see below) have somewhat greater chances. Some skill levels increase as they rise in level, again depending on class.
I stole these rules because they seem entirely natural assumptions to make that all players would have at least a minimal chance to perform these skills, and some of them should obviously increase for certain classes as they go up in level. This makes these skills easy to use and modify on-the-fly during play, something I found difficult to do with 2nd or 3rd edition versions of skills.
Again, from Labyrinth Lord/B/X I stole the Morale & Recruiting rules. These exist in a rudimentary fashion in S&W, but I was always more pleased with how they were implemented in later editions, and I use them in other ways then originally intended. I also use them to determine if your hireling or henchmen does what you intend them to do, as well as assigning a ‘Morale’ score for patrons of the party or characters, to determine how easily the NPC will provide aid upon request. Charisma, as usual, provides a bonus, which makes this it much less of a ‘stat dump’.
For Combat, I stole the Target 20 system, found here in its original iteration, I believe.
Delta’s brilliant system allows us to use original AC numbers (the so-called descending system) with an Attack Bonus number, which strikes me as the best of all possible worlds.
To successfully attack, roll 1d20 +Attack Bonus + AC + Modifiers (from strength, magic weapons, etc.). If the result is greater than 20, you hit. This duplicates the original mathematical algorithm, without look-up tables.
Your attack bonus will vary by class and level, which means you only need to know your total modifier, plus the AC of the opponent, to determine if you hit. Very, very elegant.
That said, I don’t use Delta’s system for anything but combat, finding saves (for example) in Swords & Wizardry to work quite well as they are.
Finally, I don’t use the multi-classing rules, from S&W, instead, I use race as class. I have always hated multi-classing in D&D, especially since my 3.5 experiences. Therefore, everyone has one class, even if these classes are heavily modified. More on that in the weeks to come.
Next: A real Vancian magic system.