The Iron Brotherhood Betrayal
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The Iron Brotherhood Betrayal took place long ago, when the Mercenary Army was not part of the Terran Dominion. The Mercenaries and The Iron Brotherhood were once strong allies. At one point of the war, The Iron Brotherhood joined the Terran Dominion in a conquest for power. They surprised many Mercenary Outposts and killed a great number of Mercenaries, who had willingly let them through the gates.