Warjacks, or 'jacks for short, are techno-magical constructs designed for waging war. They are, in general, powered by a coal-burning steam engine and guided by an arcane computer-like 'brain' called a cortex. Heavily armored and often carrying over-sized weaponry, 'jacks fill a role similar to traditional military armor such as tanks and artillery. Many times more durable than normal troops, they pack a harder punch as well. They are also, however, far more costly than troops.