A gravity-wave impactor was a weapon that quickly and destructively compressed matter into a compacted fused state. A weapon resembling an impactor was used by the Invisibles faction during the Chelgrian Caste War. Its effects were too fast for a Soulkeeper to save its owner; furthermore the weapon was tuned specifically to destroy Soulkeeper-scale devices. This tuning prevented it from destroying larger, and older, forms of personality-storage substrates. The compacted fused material produced from the internals of the Chelgrian privateer Winter Storm was glossy and glass-like.