Requirements for chimaera capital ship event
I have yet to see any return of said event and I was able to acquire several tiers worth of blueprints for it. Now I can't remember what the requirements are for this event. All I do remember was that...
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Each tier requires Ghost, Phantom II, and Home One specifically, and three other Rebel ships. All at whatever star count that tier is—so all at 5* to unlock, all at 7* for completion.