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The rare Mk5 engines are available in Supercharged, Equalized or Sidewinder configurations, just like the regular engines (Mks 1-4). They are built from 10 Rare Engine parts that may drop as loot from destroyed fighters. A mission is not associated with this crafted itemdropped part.
The 10 parts are crafted into a "Rare Engine" and the crafting may be done repeatedly. Since parts drop randomly and the precise part that may drop varies too, it can take a while to gain a complete set. By which point, you may be close to owning multiple sets.
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