But this article in WD #110, Paul Murphy's "Morglum's Marauders", could be adapted with little work to any RPG that has orcs in it. Here's the basic set-up:
Morglum's Marauders are the Old World equivalent of the motorcycle gangs which, according to movie lore, terrorise much of the United States' West Coast. Ugly, foul-tempered, and even worse-smelling, they represent the pinnacle of Orcish civilization.The tension in the scenario centers around the simple fact that a party of average WFRP characters would get absolutely slaughtered in a stand-up fight against a hundred organized humanoids. Basically, imagine taking out these guys as the mission of a handful of first or second level D&D characters and you can see the scope of the problem. Because Morglum doesn't trust his officers and desertions are common he only occasionally let's part of his army out of his sight. And they only pick on defenseless villages. The players are going to have to be extremely clever to beat these orcs.
Based in an Orcish mountain-range (located conveniently near to your campaign area), from time to time the Marauders sally forth from their hidden stronghold to terrorise nearby Human villages. Though their exact numbers vary from excursion to excursion, the Marauders are composed of around eighty Orc foot soldiers, a dozen Gobbo Wolfriders and twenty or so Snotling slaves (and emergency food supply).
Obviously you can easily steal the gist of the scenario and do your own thing with it, but if you get a chance to lay eyes on the article I recommend checking it out. The writing is fun, full of GW's characteristic wholesome black humor, in the "orcs are bastards, but funny bastards" sort of way. I particularly enjoy this random chart for determining what sort of trouble the orcs get up to when Da Boss isn't watching.
Orcish Malingering Table
Roll a D100 on the following table whenever an unsupervised bunch of Orcs fail their Leadership roll.
01-14 Horseplay: Several Orcs are engaged in a fierce brawl, while others place bets on the outcome. The fighters take D3-1 Wounds during the conflict.
15-28 Roughhousing: Like Horseplay, except that the Orcs use weapons. Fighters take D6 Wounds, bystanders take D3.
29-43 Foraging: The Orcs go off and look for something to eat. If guarding the supply train, D6 Snotlings disappear mysteriously.
44-58 Pep Rally: Some Orcs hold a competition to see who can come up with the best derogatory terms for another unit [in the Marauders]. If the other unit comes within hearing distance, see Roughhousing, above.
59-74 Furlough: The Orcs are off somewhere, catching a kip*. They reappear when the GM sees fit.
75-89 Bull Session: The frustrated Orcs plot to kill Morglum and take over the Marauders. Note: they never have the guts to carry it out.
90-00 Sick Leave: The Orcs decide that they have contracted some horrible sickness from exposure to all that unhealthy fresh air and sunshine. They go to Morglum and make elaborate pleas to be allowed to go home and die. Morglum listens sympathetically, knocks a few heads together, and sends them back to their unit.
*Dear Brits: What's a kip?