Lefty debuted in Underground, where he was sent alongside Righty to fight Jinja when the latter challenged Mr. Black to a fight with no Monsuno, but both bodyguards were knocked out by Jinja. Later, Lefty and Firewalker battled against Jinja and Charger in the subway, but Lefty was defeated.
In Failsafe, he and Righty were confronted by the Desert Wolves at Chef Syd's new restaurant. After a short battle, Lefty and Righty lost and had their Monsunos "liberated".