After Sarissa Theris stole a kett data module containing a copy of a map of hidden routes through the Scourge, The Valiant and the Decimation were sent to track down Ark Leusinia and return the module. This led to a long-running game of cat and mouse, as every time the Leusinia followed the map to escape, the Decimation was able to trace its movements and find it because they had access to the same data. The Leusinia would then escape again, but take on fresh damage and kett boarders with every encounter.
Pathfinder Ryder located the Leusinia and helped restore its power. Before the Leusinia could jump away, the Decimation arrived. The Valiant personally boarded the Ark and fought the Pathfinder, but upon being defeated, ordered the Decimation to destroy the ark, before Sarissa pushed him out into the vacuum of space. Sarissa and Cora Harper then used their biotics to deflect a barrage from the Decimation's ship back at it, destroying it and the Decimation.