While bantering with Zak at Playing D&D With Porn Stars (NSFW; EDIT: Zak turned out to be a missing stair and then a very well known serial abuser years after this was posted), I came up with a quick-and-dirty system for handling 3rd Edition NPCs:
(1) Give them an arbitrary number of HD. (Let’s say in d8s.)
(2) Assign them an array of ability scores.
(3) Figure out their AC. (Assign a number or do armor + Dex.)
(4) Figure out how much damage their attacks do. (Assign a number or do weapon + Strength.)
(5) Done.
In play, pertinent stats can be easily calculated off HD:
Melee Attack: HD + Strength modifier
Ranged Attack: HD + Dexterity modifier
Saving Throws: 1/2 HD + ability modifier
Skills: HD + ability mod
You could also, obviously, precalculate these values if you were feeling fancy. But where this is really useful is when you’re trying to keep up with your PCs on-the-fly. If you can quickly jot down:
HD 7; Str 16, Dex 12, Con 14, Int 11, Wis 10, Cha 8; plate, longsword
Then you’ve got enough information to run the NPC.
If you want to class up the joint a little bit, it’s pretty easy to slap a few class abilities on there. And here’s how you do spellcasters:
(1) Look up how many spell slots they have.
(2) Write those numbers down.
(3) Open your PHB to the spell lists and pick spells as they cast ’em.
So you might jot down:
Wizard 8; Str 8, Dex 14, Con 10, Int 18, Wis 14, Cha 11; 4/4/3/3/2
And that’s enough to run the encounter.
It’s a pity that old school monsters didn’t include ability scores, because otherwise this system would allow you to instantly convert them on-the-fly.
I just note unusually high or low ability scores and assume anything un-noted is 10 or 11.
I make up the ability score the first time it’s required; usually my NPCs start out as “m. dwf. ftr1 12hp ac16/10/16” and expand from there on the empty lines I leave myself. That way, if all the PCs do is talk, I only need to pick a Cha and Wis score for the NPC; if they fight him, he needs Str or Dex and Con. A very lazy method, but flexible as well.
I do have a fast, loose, and dirty method for making 3.Xe/PF compatible NPCs that can vary by type:
I expressly avoid using these rules for anything other than mooks, minions, or whatever. Luckily, I haven’t needed to use these rules ever since switching to d20 modern for my current game (they statted out virtually every NPC I could think to use in the primary book and the menace manual), but I’ve used these rules or ones like them in order to conjure up a last-second NPC encounter, making minor adjustments whenever necessary depending on the race (the below stats assume something like a human with no significant stat boosts/penalties or special powers.
I don’t set these in stone, as I add and subtract abilities and such as needed (like initiative) based on my rough concept of what the group is and other variables.
All:
Skills/Feats/Class Powers: Based on my last-second concept of the warrior. My have other special abilities depending on race. Relevant skills used to oppose the PC’s skill checks are 15 + CR of creature. Determine feats on an as-needed basis – being careful not to give them everything they need.
Spells and save DCs are also used on an as-needed basis – pulled directly from the PHB or memory – being careful not to exceed what might be expected of a challenge of that particular level (not using 7th level spells from a CR 10).
Save DCs: 15 + Spell Level + Spell Focus.
Saves are made on a 8 or higher for good saves and a 13 or higher for bad saves.
Melee-ist: (Fighter-Types)
AC: 20 + CR
HP: 15 x CR
To Hit: 5 + CR
Secondary Melee: (Rogue Types & Cleric Types)
AC: 15 + CR
HP: 12 x CR
To Hit: 5 + 3/4CR
Casters:
AC: 10 + CR
HP: 6 x CR
To Hit: 5 + 1/2 CR
So, for example, if the 10th level PCs are a mixed group and they decide to shanghai a rich but well protected merchant that was totally unexpected, I might have him be protected by four warrior knights and a caster.
The warriors would be sword and board based (protectors) so I’d figure their damage would be 1d8+10 (let’s say – they’re carrying longswords and using plate mail and large shields) and would have defense-focused feats – including the combat expertise chain with a focus in disarming.
Initiative +2 for the group (they generally aren’t dex-focused).
So…
Warriors: 150 HP, 30 AC, +15/+10 to hit w/ 1d8+5 damage each hit.
The Caster: 60 HP, 20 AC, +10 to hit, Save DC 15 + Spell Level (+1 abjurations/illusions) – likely an abjurer or illusionist so would have a number of spells/day based on a specialist mage with a 20 INT.
It’s worked well for me as long as I don’t share the specifics on these character’s stats. Treasure is rolled normally, but they’d have whatever equipment you described them as having (the warriors would have plate mail and heavy shields, despite carrying whatever loot you roll for them.
The need for ‘on-the-fly’ NPC generation has always puzzled me. And made me very suspicous of GM’s (like Zak) who find these ‘tricks’ to whip things out on the fly.
Since the very beginning of the hobby there have been plenty of resources for NPC stats (anyone else remember ‘Rogues Gallery’?) and even earlier books of computer generated NPC statistics that could be used for GMing games. I’m sure I’m not the only person that wrote one in GW Basic!
Today, with the dozens of NPC generators on the internet why would anyone EVER need to generate an NPCs on the fly?
I don’t use a computer at the gaming table. And even if I did, the time required to open up an NPC generator, generate an appropriate NPC stat block, transfer it somewhere permanent, and then tweak it as necessary is still laborious compared to the method described here.
I am curious what you could possibly find “suspicious” about a GM becoming more effective at their craft. Do you live in some kind of paranoid hell hole?