The HK-87 assassin droid was a model of assassin droid. During the time of the Galactic Empire and New Republic, they served as bodyguards and enforcers. Magistrate Morgan Elsbeth utilized two such droids in her army while ruling over the city of Calodan on the forest planet Corvus. When the former Jedi Ahsoka Tano and the Mandalorian Din Djarin worked together in an attempt to defeat Elsbeth, the magistrate sent the two droids to assist in hunting down the attackers. One of the two droids was destroyed by Tano, while the other was shot by Djarin after Elsbeth was defeated, freeing the citizens of Calodan.