The MRK-3 Assassin Prototype droid, a newer version of the Assassin droid, was manufactured by the Chromium Kings and is thought to have belonged to Khundu. These droids shared a similar appearance with the Mataou Hutt security droid. Only one Prototype is known to have existed, and it met its end at the hands of The Smuggler, dispatched by the Ivax Syndicate to silence the Chromium Kings' boasting regarding a recent transaction involving "specialized" droids.