Rover was one of the Original Mark 1 Sentinels that was left outdated and partially destroyed. At some point, the X-Men met Polaris, who repaired and employed the Sentinel, whom they named Rover. Marrow was good friends with Rover, often helping him to destroy the more modern Sentinels, and scrapping them to perform further repairs to his badly-damaged condition.
After Bishop planned to use Rover to distract five Sentinels, Marrow became enraged and ran away with Rover, however they still ended up aiding the X-Men, Rover destroyed two Sentinels, before getting a hole blasted into his chest, and a hand blown off. The Sentinel continued to fight and killed the remaining Sentinels, however he was finally get killed himself when a pack of the smaller Wolverine-based Sentinels climbed all over Rover. His final words to Marrow were telling her to run before his demise.
Powers and Abilities
Rover possesses weapons that are common among Sentinels
Rover had hand based lasers that could be fired at will, and the energy from the stub of his hand formed a blade which could be used to cut down his enemies. He could only say the word DESTROY until his death, which he finally said another word 'run'.