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X3: Farnham's Legacy allows you to chose from different pre-defined gamestarts enabling you to decide how fast or slow paced your start in the universe will be and what challenges you will have to overcome. Thereby, the gamestart you choose affects: Your initial pilot name (you can change this in-game), your character's race, your initial starting location, your initial cash, your initial ship(s), and what equipment and upgrades are installed, the initial assets you own and your initial reputation with the different races. The start also affects, whether you will be able to play the main plot.
Some of these starts are unlocked from the beginning, while for others you will first have to play through the main plot of X3: Farnham's Legacy in order for them to get unlocked. Furthermore some starts have additional short-term difficulties, such as extra tasks to complete in order to receive certain items. If none of the predefined starts suits you, the Custom game allows you to define your own starting parameters.
Note: Apart from the above, the game start gamestart has no effect on combat difficulty levels, rewards, or anything else in the game.
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