The Cervello explain how the Elettrico Circuit for the Lightning Ring Battle works. Excited, Lambo runs toward the battlefield, dropping his horns in the process. Gokudera writes "dumb" on the horns and gives them back to Lambo, who is then instructed to go to the battlefield, where Levi A Than has been waiting for two hours. Tsuna and his Guardians form a group circle. Worried about Lambo, Tsuna tells Lambo that he doesn't have to fight, but Lambo picks his nose and says that he's invincible. Tsuna gives child-Lambo the horns from Adult Lambo and with that, the Lightning Ring Battle commences.
Lambo starts crawling through the Elettrico Circuit, thinking that it's a playground. As the circuit becomes electrified, Lambo is struck with a blast of electricity. Although Lambo cries from the pain, he didn't die due to his lightning-resistant Elettrico Cuoio. Levi A Than charges forward and mercilessly beats Lambo with a Parabola. Lambo uses the Ten-Year Bazooka and summons up the fifteen-year-old Lambo. The older Lambo, determined to defeat Levi A Than, uses Thunder Set. The older Lambo charges at Levi A Than with his Elettrico Cornata, but is stopped by Levi's Levi Volta. Just before Levi A Than can finish Lambo off, the older Lambo uses the Ten-Year Bazooka. As the smoke clears, a man surpassing the power of Child and Adult Lambo appears, the 25-year old Lambo.
Note: Bold + Italicized = First Appearance