Adelphine Cluster

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The Adelphine Cluster was an isolated star cluster on the galactic rim. Interstellar dust clouds concealed it from the rest of the galaxy. It was the home of the Averon Union. When humans colonised the cluster, there were conflicts with the Union, but they remained mostly minor. However, fifteen hundred years after the humans arrived, the seriousness of the disputes suddenly increased and ultimately led to war. (PROSE: A Device of Death)