Lost Number Roidmudes are mechanical recreations of Roidmudes lacking a numerical designation and supporting antagonists in the 2014 Kamen Rider "Movie War" crossover film Kamen Rider x Kamen Rider Drive & Gaim: Movie War Full Throttle.
Unlike regular Roidmudes, Lost Numbers lack the Roidmude cores that give Roidmudes their sapience, instead acting as mindless disposable foot soldiers for whoever created them.
After arriving on Earth, Megahex at some point copied the data of the Roidmudes and began producing Lost Number recreations of them. A group of Lost Numbers were seen guarding Megahex's ship, but were destroyed by Kamen Rider Ryugen during his attempt to rescue Mai.
During his confrontation with Drive, Kamen Rider Lupin used his Lupin Gunner to spawn a trio of Lost Number Roidmudes created from the data of Roidmudes 014, 020 and 061, whom he had destroyed earlier. The Spider Type was be destroyed by Drive while rescuing Kiriko while the Cobra Type and Bat Type were destroyed by Mashin Chaser's Tune Chaser Spider.
Later, numerous Lost Number Roidmudes were among the massive army spawned by ZZZ Megahex, which included mechanical recreations of Elementary Inves and Kurokage Troopers. The army fought against an alliance between the Kamen Riders and the Heart Roidmude, Brain Roidmude and Mashin Chaser. The Lost Numbers deactivated along with the rest of Megahex's army after Megahex's core was destroyed by Gaim and Drive.