He first appeared in "I Think His Name Was Baxter Stockman," where he was seen trying to break into a building in a shriveled suit of armor. The Turtles stopped him, but Stockman came into possession of Donatello's T-Pod (which has a military-grade artificial intelligence chip) and incorporated it into his armor. This results with the armor upgrading itself into a larger size, proving him a competent threat to the Turtles, who still expressed sympathy for the hapless scientist. During "Mousers Attack," he was shown to have created the Mousers to steal electronics from underground. But when they interfered with the Foot Clan's new plan to kill the Turtles, he was captured by Dogpound and brought before Shredder, who forced him to join the Foot Clan, believing his genius to be a useful asset. However, by "Baxter's Gambit," Stockman became tired of being regularly harassed and threatened by Dogpound and Fishface, so he sought to eliminate all of his enemies at once, and trapped the two with the Turtles in a deadly maze. He was defeated when the two groups unexpectedly joined forces against him, and he fled the Foot Clan.