The Space Marines are the greatest of humanity's warriors, fierce soldiers that have been subjected to intense training, genetic modification, and psycho-conditioning. Their fleets are experts at close-ranged battles, sporting well-armoured ships and specialize in aggressive boarding techniques. In addition, they have access to two unique faction traits which makes them immune to insubordination mechanics and gives them the ability to prioritize their attacks on different subsystems when boarding. The Space Marines DLC includes 5 different Space Marine chapters.

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