Landmine began as an Autobot traffic warden before the Autobot-Decepticon war escalated. Millennia of combat forged him into a seasoned soldier and mentor; he instructed younger Transformers like Mudflap and taught the combat technique Metalikato to Optimus Prime. When Unicron threatened Cybertron, Landmine accompanied Rodimus into exile, serving as his right-hand soldier and personal bodyguard alongside partner Prowl. He vowed to protect Planet Q but failed when Unicron consumed it. Years later, he rejoined Rodimus to help Alpha Q restore destroyed worlds using Unicron's power, though he occasionally questioned their mission's agenda. Landmine eventually transferred allegiance to Optimus Prime after Rodimus surrendered leadership. During Cybertron's black hole crisis, Landmine served under Optimus Prime during the evacuation to Earth. Starscream defeated him in battle and blasted him toward the black hole. Vector Prime intervened, opening a warp gate that deposited Landmine, severely damaged, on Earth. Human children Lori, Coby, and Bud Hansen discovered him. Coby assisted in repairs while Landmine recounted the conflict. Despite injuries, he defended the children from Thundercracker until Optimus Prime arrived. Recovering, Landmine oversaw the Autobot Earth base but chafed at being unable to search for the Omega Lock. He impulsively scanned a bulldozer as his new Earth alternate mode before fully healing. Later, he intercepted Starscream's attack aimed at the children and Mini-Cons, awakening his "Cyber Tempest" power by summoning a Cyber Key to defeat Starscream. Landmine participated in missions to the British Isles and Velocitron to locate Cyber Planet Keys. He confronted former protege Mudflap after Mudflap joined the Decepticons, persuading him to rejoin the Autobots. Harnessing Gigantion's Cyber Planet Key energy, Landmine grew to colossal size and defeated Starscream decisively. His bond with the Hansen children, particularly Coby, profoundly impacted him. Initially focused solely on saving Cybertron, he grew to value Earth equally due to their friendship. After Galvatron's defeat, Landmine and the redeemed Mudflap departed with Wing Saber to investigate Starscream's apparent survival in deep space. Personality-wise, Landmine lives by a soldier's code of honor and loyalty. Gruff yet warm-hearted, he is determined but sometimes overestimates his capabilities in battle. As one of the oldest Autobots, his systems require frequent maintenance, yet his resolve remains undiminished.