Doom was a Clone Commander who served Jedi Generals Tiplee and her sister Tiplar in the Battle of Ringo Vinda during the Clone Wars. Aided by Anakin Skywalker and the 501st Legion, Doom and his unit engaged droid forces led by Separatist Admiral Trench aboard the space station orbiting Ringo Vinda. During the battle, 501st clone trooper Tup was seized by a premature activation of Clone Protocol 66 caused by a malfunction in his clone inhibitor chip, and murdered Doom's Jedi General Tiplar. Droid reinforcements capitalized on the disarray caused by Tup's betrayal, forcing Doom and his men to retreat under fire and investigate their general's murder.