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Its true motivations remain unclear, but since the cataclysmic event called Starfall (for which it may be responsible) it has spread its control across almost the entire surface of Holdara, leaving the surviving Holdarans trapped in Lighthaven beneath the Celestial Tower and faced with the daunting task of driving back the Nanovoid forces to take back their homeland. 

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Origin 

The “dark particles” that make up the Nanovoid were originally part of the heliolith that the Celestials brought through the Lightstar. Like DNA in our world, these particles allowed things similar to plants to grow and replicate. 

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