Derren said:
Somehow I fail to see how you are able to stuff that many soldiers in such a small space so that everyone is affected by frightful presence.
That "small space" is a radius of 30 feet per age category. For a mature adult red, that's 210 feet. Not so small... so let's talk about visibility.
The dragon will obviously be attacking at night. We'll be generous and say shadowy illumination, although an overcast, moonless night in a pre-industrial setting is a lot closer to total darkness. Hence, the dragon has concealment as it comes in, enabling it to Hide. It will of course cruise in at a leisurely 150 feet per round so as not to take any penalties due to movement.
At a range of 210 feet, the archers have a -21 to their Spot checks. A mature adult red with no ranks in Hide has a -8 Hide modifier due to size penalties. So the net result is that if most of the archers have +2 Spot (typical for a 1st-level warrior who put some cross-class ranks in), they have to roll 11 points higher than the dragon. A bit of number-crunching reveals that 11.25% of the archers will spot it at that range.
But wait! It gets better. Only the archers who are exactly 210 feet away will have an 11.25% chance to spot. The chance drops rapidly as they get further off. At 220 feet, it's 9%. At 230 feet, it's 7%. At 300 feet, they can't see it at all.
End result: Dragon glides in toward the city. We'll be insanely generous and suppose that all 500 of your magic-arrow-armed archers manage to get in the perfect "sweet spot" at 211 feet. On average, 56 of them will spot it and shoot. Of those, three will hit. 3d8+3 damage, woo. The dragon notices the arrows coming at it and angles in that direction, raking your archers with its frightful presence. Half the archers flee in terror, and the dragon is now beyond sight range for the other half; the only archers who can see it are those who already spotted it in the previous round (since it hasn't done anything to break line of sight).
Another volley from the guys who saw it, scoring maybe another two hits for 2d8+2. The dragon comes back. More terror. Then the dragon belches fire, killing a couple archers who made their saving throws, and setting a couple of buildings aflame. One round of arrows from the 25 archers who made their saves scores one last hit for 1d8+1. After that, the smoke will provide total concealment for the dragon as it burns and ravages... no more archery.
So, let's review. You have been given the following ridiculous advantages:
--Knowledge ahead of time that the dragon is coming
--Arrows pre-buffed and distributed to 500 archers
--Archers perfectly positioned to shoot at the dragon from 211 feet
With all these breaks--which you would hardly be likely to get in a real dragon-versus-city scenario--you managed to inflict 6d8+6 damage, averaging 33 damage, to a mature adult red dragon. Instead of 312 hit points, it now has 279. Oh noes. That's going to cripple it soooo badly when the PCs come to engage it.
Derren said:
Historical knowledge doesn't automatically mean magical knowledge.
Knowledge (Arcana) bloody well does. And historical knowledge is often very useful to a wizard.
Derren said:
Don't forget that this knowledge has to be so interesting for a wizard that he is willing to deal with a dragon.
You say that like it's a bad thing.
Derren said:
If you mean "combat encounter" with "enemy" then you are correct, dragons do not require spells for combat. They require spells outside of the combat to be effective masterminds. Dragons can't really be subtile without using hordes of minions or magic and to influence whole kingdoms subtility is required because unless dragons are made much stronger than in 3E they can't take on an entire kingdom.
No, they don't. A dragon is perfectly capable of being a mastermind without spells. It just has to, y'know, mastermind stuff. And as long as it's got a few human or human-looking agents to deliver its orders and carry out business transactions, it has all the subtlety it requires.
Derren said:
From the answers in this thread so far it looks to me that most DMs sacrifice cohesion for plotwriting.
No, we simply give a creature with genius-level intelligence credit for not being a total moron. Contrary to your repeated assertions, it is perfectly possible to be a powerful mastermind without being a spellslinger. Lots of people have demonstrated this in detail. Your counter-arguments have done no more than nibble at the edges of a few of the less well-constructed examples.
Derren said:
And the reaction time would be much too slow to do something against fast moving adventurers or NPCs who use magic for communication.
It's not hard to find a couple of minions who can
teleport. Heck, if you can get a mid-level evil outsider working for you, a lot of them can do it at will. Of course,
teleportation will be much less common in 4E... but that applies to the adventurers/NPCs too.