I beg to differ. But I think we're having a playstyle disconnect here and I think you're reading too much into my hyperbolic statement about shivering. I get the feeling that you think being nasty is in itself unfair and I feel that you are assuming motives that aren't there.
I have no problem with being nasty. I'm on record as stating that I think 'Tomb of Horrors' is a fair (perhaps even preeminently fair) dungeon. Nasty doesn't bother me. But the point is that kobold minions aren't nasty and you can't make them nasty. Any attempt to explain how nasty they are will only emphasize the limited role they actually play in the nastiness. The real nastiness you are going to through at the party is going to be the truly evil terrain that you force the party to fight in. The kobolds themselves aren't capable of doing much of anything, which is one of the reasons I reject the myth of 'Tucker's Kobolds'.
Ah, but that's the charm, isn't it? It's not gonna be waves of minions. The trick is to outsmart the kobolds' tactics.
If the kobold's tactics can be 'outsmarted', then its just going to highlight how worthless of a foe the kobold is. Again, the 'Tucker's Kobold' of myth depend heavily on the DM ruling in the NPC's favor solely because they are NPC's.
The only way this works without DM 'cheating' is to take the kobolds out of the equation. Basically, you have to deny line of sight on the kobolds at all times, and never attempt direct attacks on the PC's. Arrow slits are for suckers, because the PC's will still be about 5-10 times more likely to hit a kobold on the other side of an arrow slit than the kobold will be to hit them. If you actually were to have enough arrow slits hiding kobold archers to be a relevant threat, you'd be bored and so would the players.
There is no trick to it; there is no cleverness on the kobold's part. The kobold's aren't 'smart'. Smart kobolds probably wouldn't even fight PC's - they'd offer them tribute, beg to be left alone, and promptly deliver to the PC's whatever gizmo that the PC's were seeking in their lair. You can't even give enough tactical advantage to kobolds to make them worth anything. All kobolds are in this case is trap triggers with the in game flavor of being sentient. Smart implies adaptability, but in a class/level based game kobolds don't have enough game resources to be adaptable even if you invest all your personnel intelligence in them. Instead, you are merely designing a death trap on behalf of the kobolds and then allowing them to be somewhat participatory in its workings. The force to be reckoned with is the lair. That's the real foe. The kobolds are worthless even as cannon fodder.
So, the basic situation is this. There is an oblong dome shaped hill in the moors roughly 12 miles across and about 1800' of elevation change. The dome itself is composed of three layers of stone, an upper layer of sandstone or other hard semi-permable rock, a middle layer of limestone, and a lower layer of mixed metamorphic rock rich in layers of ancient coal and siderite. Whereever the upper stone layer has cracked, it leaks water into the lime stone layer, with the result that the limestone layer has eroded into sloping labyrinth with passage ways that follow the pattern of the cracks above. These passages are on average triangular with a base about 5' across and an apex about 20' high. However, more irregular passages can be found where leaking water joins to form small stream beds, which erode passages into high meandering retangular forms, often with upper (hidden shelfs. Numerous entrances to the various - small and large - cave systems can be found along the perimeter of the hill. The largest of these complexes - one with several miles of passage way - is inhabited by a comparitively prosperous large and self-sufficient community of relatively advanced kobolds.
These kobolds live deep in the hill, and prosper because they are able to work the rich veins of coal and iron ore safely. With this they are able to manufacture reasonably good steel for their own use, as well as trading the surplus to a nomadic band of hill giants - too lazy and large to work the mines - for things that they cannot easily manufacture themselves. They eat game that they can hunt among the bogs of the surrounding moor, as well as cave crickets that live on the fungus farms the kobolds maintain in the abandoned portions of their mines, and have plentiful natural water from the springs that form where rain water perculates down to their depths. The industrous kobolds have even damned the small streams that result, to form a large underground pond in the heart of their realm, and with this power a waterwheel which turns the trip hammers that they use to pound their ore and hammer their steel. For this reason, those on the surface of the hill report that they can hear a faint tapping or banging coming from within, and for this reason the hill is known as 'The Ringing Tor'.
Ok, so that's the set up. I've provided my band of kobolds with the resources they need to kill or at least harass PC's and withstand a seige. We have a fortress which will be difficult to either surround or assault, and abundant replinishable natural resources. Plus we have an outside supply chain which, even if we need to depend on it, will be dangerous for the players to disrupt directly. Kobolds may be well below the PC's level, but the band of 20 hill giants that they trade with is not. Inside their fortress we've got terrain that let's us set up the indirect warfare we wish to perform and which I'll now describe.
In addition to mining the veins of ore, the kobolds have spent the last few centuries fortifying their home. To do this, they've connected the natural cave passages with a network of their own tunnels worked patiently into the soft limestone. These tunnels are all more than 15' off the floor of the natural passages, and connect to concealed 'balonies' and 'murder holes' worked in the upper walls and ceilings. The kobolds defensive strategy is as simple and cowardly as they are. Rather than worry about fighting, or shooting bows, or any thing of that sort, the kobolds simply take as large of a rock as they can lift or push, and throw it into the natural passage way below and hope for the best. If they crush a foes skull, then well done. Otherwise, they just move on and keep trying. In places with ceilings high enough that torch light does not easily reach, they've prepared the defenses by storing several hundred pounds of rock in hammocks suspended from the roof, which can be released to dump their contents by simply yanking a knot or tipping them with a long wooden hook.
The defensive tunnels are never more than 4' high and 4' wide, and in many places they are a good deal smaller. Narrow places - usually no more than 1' wide and 2' high, but often less, are blocked with simple stone portuculis consisting essentially of a 100lb block with a hole bored into it, a rope on a pulley for lifiting it, and a stone peg which can be jammed into the rock to prevent it from being lifted. In this way, they can isolate portions of the defensive tunnels that get invaded, and move deeper into complex. In response to a persistant effort, they'll build a coal fire in a tunnel and fill it with smoke, and if that fails, they'll use their knowledge of mining to collapse the tunnels surrounding the penetrated area.
While most of the caves are in basically their natural state, any of those that lead to their village directly are blocked up with barriers of stone and concrete. Hidden 'gate houses' consisting of large baskets which can be lowered from trapdoors in the roof allow access to the defensive level itself, and in turn, several layers of porticulis protect the village level from access through the defensive tunnels. In several positions, the kobolds have built simple barbicans that control access to the straightest and most useable tunnels in the labyrinth. These consist of thick walled cylinders of stone and concrete which enclose a mangonel, oriented so that it can fire through a loophole straight down the passage for up to a hundred yards without really having to be aimed in any fashion.
Sentries are positioned in various places through out the caves, hiding in the darkness and peering through a peephole into the natural passage below. These never dare attack by themselves, but instead upon seeing the tell tale signs of fire light or hearing voices other than the hiss of kobolds will scurry back to fetch their fellows. Thereafter, they will endeavor to track the movements of invaders by sound and light, without risking direct observation (and the resulting spot check it would give to invaders!).
As a last resort against an determined invader, the kobolds will open spill ways within their village, which in turn will send a portion of their resivore racing down the passage of their choosing in a wall of water that will hopefully batter and drown any one that has penetrated too deeply into the hill.
The village itself contains their work shops, furnaces, armories, hatcheries, farms, store houses, mills, temple, dungeons, living chambers and entrances to the mines. These are all made to kobold scale and defended in a manner similar to the outer defenses. Political power is shared between a priesthood of adepts and clerics that have the final say on all matters of peace, and who pass on the lore of the gods in mining and crafts to the tribe, and a war lord who makes the decisions concerning war. The kobolds are all closely related and so long as it doesn't involve acts of bravery, will do their best to protect and care for each other, ferrying any wounded back to the temples and working together to stop up any gaps in the defenses.
