S7-1Y was an assassin droid created by the Empire in 4 ABY. It was sent on several missions around the galaxy, rooting out Rebel operatives and eliminating seditionists. On Wrydrock, on a mission to destroy a former Separatist in 17 ABY, it was captured by members of the Separatist's gang, the Droideka Killers. Its memory was wiped and it was put in storage, seeing only Marthrull Strayfiend and his brother Mathias, who were in charge of reprogramming it. When the gang's leaders were killed and the gang scattered by Boba Fett a few days later, the droid was locked in a storage room. The two brothers recovered the droid and it served aboard the Hyperius, a ship owned by the boys' uncle Tull Strayfiend. The droid relearned its assassin capabilities following Tull's death and became the Strayf