The YVH-Ms were a type of mouse droid designed by Lando Calrissian with the specific purpose of locating and pursuing Yuuzhan Vong spies. These droids possessed a unique capability: the ability to detect and trace Vonglife signatures. Notably, a group of YVH-Ms played a crucial role in uncovering all of Nom Anor's network of spies situated on the planet of Mon Calamari during the year 28 ABY.