Jürgen Hubert said:
I used to do a lot of preparation for NPCs and monsters. But then I asked myself:
"Will the players ever notice if I just fudge things?"
It was quite a revelation when I realized that the answer was "no"...
Heh. The last several sessions in my game have involved big combats with classed NPC allies, classed NPC enemies, monster enemies, and innocent bystanders. They were a bear to prepare for -- try making six interesting half-elf wight classed NPCs, even with Jamis Buck's generators, and see how long it takes!
Finally, last session, with yet another of these huge set pieces, I changed my tactics. I did a mostly-full-prep on the two most important NPCs, copied down the stats for the monsters, and ran everyone else on the fly. Sixth-level fighter? he's got, let's say, a +9 to hit, does 1d8+4 damage, and has 45 HP.
Even for the major ones, I made up spells on the spot. It was fun for the cleric to try to summon an air elemental, so she had the appropriate spell prepared.
It worked very well, and freed up my planning time for omens, atmospheric NPCs, and ritual details.
Daniel