Gameplay
The Atreides House has no military or spice mining units. Soon in the game, Paul must meet the closest Fremen leaders and convince them to work for him. In the beginning, they will only agree to work as spice miners. After Paul is introduced to Stilgar, the tribes will agree to work as either spice miners or military soldiers as Paul chooses. After he is introduced to Liet Kynes, the tribes can also take ecology as their occupation.
All tribes will increase their ability in their chosen occupation. Spice prospectors do so by spice prospecting in many sietches. Spice miners do so by mining spice. Military troops do so by training in their sietches (if Gurney Halleck is in the same sietch they increase their ability at a faster rate) or successfully completing military missions.
All tribes except the spice prospector tribe can change their occupations, although it is better to keep a tribe in the same occupation. Experienced spice prospectors can prospect spice faster. Experienced spice miners can mine more spice. Experienced military troops are more effective in military missions. However, there may be situations where changing a tribe's occupation is required. For example, if a large number of military troops training in a sietch is captured by Harkonnen forces, more military troops need to be raised from the spice or ecology troops to liberate the sietch and rescue the captured troops.
Although the Fremen agree to work for the Atreides in order to depose the Harkonnen, if there are tribes from both hemispheres in the same sietch, they will quarrel and refuse to work (this seems to happen frequently with the spice miners). Morale (affected by contacts with Paul, Atreides advancement in Arrakis, the progress of ecologists, and whether Chani is captured or free) also affects the speed and capabilities of the tribes.
The Ornithopter (Orni) is the default transport method for Paul until he's able to ride sandworms. With the Fremen, they are used for either moving from one sietch to another quickly or as an early warning against sandworms attacking spice miners and prevent Harvesters from being swallowed. Harvesters increase spice mining speed, and can be either bought from smugglers or found in sietches. Weaponry ranges from crysknives, laser guns, Weirding Modules and the powerful atomics, and are usually found on sietches or conquered Harkonnen fortresses.
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