Ep 1. Outbreak

In season 2's premiere episode of Ben 10: Omniverse, entitled "Outbreak," Ben and Rook are called to investigate a mysterious outbreak in Undertown. The episode opens with the duo fighting off mutated criminals in the streets, and it quickly becomes apparent that they are dealing with a dangerous virus that is spreading rapidly.

As Ben and Rook continue to fight off the infected, they discover that the source of the outbreak is a group of experimental nanobots that have been released into the city by Dr. Psychobos, one of Ben's long-standing enemies. The nanobots, programmed to turn anything they touch into cybernetic zombies, are wreaking havoc on Undertown and threatening to spread beyond its borders.

With the clock ticking, Ben and Rook must find a way to stop the nanobots before they infect the entire city. But they quickly discover that things are not quite as they seem - the nanobots have been released as part of a larger plot to take down Ben once and for all.

As they work to unravel the mystery and stop the outbreak, Ben and Rook are forced to confront some of their darkest fears and insecurities. Ben struggles to come to terms with the fact that he may not always be the hero he wants to be, while Rook faces his own doubts about whether he has what it takes to be Ben's partner.

In addition to the high-stakes action and intense emotional drama, "Outbreak" also introduces several new characters and elements to the Ben 10 universe. We meet Khyber, a ruthless and cunning hunter who has a personal grudge against Ben, as well as Malware, a powerful and mysterious being with ties to Ben's past.

Overall, "Outbreak" is a thrilling and action-packed episode that delivers everything fans have come to expect from Ben 10: Omniverse. With its strong characterization, intricate plot, and stunning visuals, it serves as a fantastic starting point for the show's second season.