A point-by-point argument, if you don't mind the format.
Moonstone Spider said:
But your tactics do rely on the Orcs sneaking up (Without any move silently or hide skills) on watchmen who most likely do have the spot and listen skills.
Don't overestimate the skills of the commoners. They have 12 skill points. As you point out, they are likely to spend a portion of those and their two feats on life-skills (profession and craft). Even if they do manage to squeak out a few for spot and listen, they won't be maxxed out. The best you would probably get is +2 to +4 for each. Call that +3 on average, and compare it to the orcs move silently score of -1 and it seems the humans have an edge until you take into account the distance penalty of -1 per 10 feet. On average (taking 10 on the relevant skills), a commoner won't spot or hear the orc until the orc is within 50 ft. Spot is impossible beyond 60 feet (for a lantern that costs 7 gold, plus oil) or 40 feet (for a torch that costs 1 copper). Of course, the orcs are setting up for a charge by then.
Moonstone Spider said:
And don't forget the village's dogs, which are useful not only for security but jobs like herding and keeping vermin away from the chickens. They have quite acute senses (For level 1 creatures) and will also bolster defenses.
So, if the humans (Who are much smarter than Orcs) apply their own intelligent tactics to defense what can be done?
First a big mean dog or two in each house. It'll be a minor drain on resources but they're useful for a lot of other stuff too. This adds a major bolster to defenses, and provides a very sharp-eyed and eared watcher for the clumsy noisy orcs.
Dogs are expensive. Guard dogs cost 25 gold, and commoners have an average starting wealth of 5d4 gold. Effective dogs (the stats of riding dogs) are much more costly (about 150 gold). The (somewhat) affordable dogs do have spot and listen skills of +5, moving the detection range out to 70 feet or so. Chancy, true. As to the combat effectiveness of dogs, that is fairly overstated, too. A dog has only a 50% chance to hit the orc, and of those hits, only one in four will put an orc out of the fight (by damage, ignoring crits, and the orc will still be conscious at zero hit points). The orcs, on the other hand, have the same 50% chance to hit the dogs, but any hit is a guaranteed kill. Similar numbers for the combat effectiveness of the commoners are as follows:
chance of a commoner to hit an orc: 40%
chance that a hit takes the orc out of the fight: 2/6 or 1/3 (1/6 to put negative)
chance of an orc hitting a commoner: 75% (not counting charges)
chance that an orc outright puts a commoner into negative hit points: 100%
The intelligence difference is less significant than you make it out to be. Only a one-point difference in bonuses. The thing that helps human commoners is the extra four skill points.
Moonstone Spider said:
Second just build a fence. One a hundred feat or so away from the house will be fine. At night you bring your livestock inside this fence and let your dogs roam around inside protecting it.
In an attack the dogs will make enough noise to raise the dead, alerting the whole village in short order as other dogs take up the call. The other villagers will be showing up in a minute or two. The Orcs have, at most, ten rounds to climb a fence, manage to kill two dogs (And the orcs can count on losing at least four of their number to just two dogs and four humans in the process), Eight humans, and loot and burn. If they can't manage to steal whatever it is they want and escape by then (They can't) the rest of the village surrounds them and kills them all.
Your combat numbers look off to me. The orcs kill an average of three humans in four swings. Humans usually take two hits to kill the orc, and hit less often. I'm figuring an average rate of extinction (at zero hit points or less) of one orc every four or five swings by a commoner. In a fight, I might even put one orc versus two humans to be a somewhat fair fight, depending on dice. In the first round, the pair would only have a 42% chance to put the orc down, whereas he would kill one of them 75% of the time.
Similarly, the dogs fall at a rate of about one every other round to a single orc, while it takes an about three or four attacks from a dog to kill an orc. (Note that these are attacks, not hits, from a bog standard orc, dog, and human commoner using a 1d6 weapon, and it ignores crits--those
would favor the humans and dogs, though, since on the orcs part, crits are "wasted damage." Against the much-more-expensive riding dog, the crits are useful to the orcs, but not so much to the riding dogs.)
A fence (assuming here that it is no higher than 10') would help the villagers, but at a +2 to their jump and climb (+3 from strength, -1 from armor), the orcs have a decent chance of clearing it in a move action. Also, at 100 feet, the listen check modifier is -9 without considering the intervening walls. This means that the orcs will largely be undetected by people in the houses until the dogs begin to bark. A smaller fenced area would be better, actually, since the dogs are more likely to hear the orcs (knowing "farm dogs" like I do, they are very likely to be right next to the house for much of the night). It would also be less expensive. Unfortunately, the dogs are likely to die quickly and without hurting the orcs too much unless there is some light nearby (thanks to the 50% miss chance from concealment due to darkness); even in shadowy illumination, there is a 20% miss chance for the dogs and none for the orcs.
(Wow, this got long.) Anyway, I hope you aren't taking this as me being antagonistic. You started the thread mentioning that 24 orcs wouldn't have a chance against a village of 50 commoners. I am just positing ways (and probabilities) that would make it possible for you to have the adventure you mentioned. Not even accounting for morale, the commoners don't have much of a chance. The orcs will probably remain in small units easily capable of killing equal-sized groups of peasants or mixes of peasants and dogs. (Don't discount that the orcs might have dogs, too.) The human commoners will not likely mount an organized defense until quite a few families have been put to the orcish falchion. Even then, the orcs kill people with savage efficiency. Each hit downs a peasant (the damage for orcs is listed as 2d4+4 versus the average commoner's 2 hit points). There is even a slight chance that the orc kills (puts to -10 hit points) a peasant outright--and in a satisfyingly gruesome manner--with either a crit (11% chance of critting each swing) or a max damage hit (about a 5% chance per swing). That
is a morale-influencing event. Any commoner in the fight has a roughly 16% chance per swing of immediately going from healthy to spectacularly slain. That compares to their 7% chance of hitting the orc hard enough to put it at zero (still standing) or 8% chance to make the orc go to dying (those numbers do, very roughly, include crits).