Albedo successfully switches places with Ben Tennyson, sending Ben to the Plumber HQ prison while he infiltrates the team.
He seeks to steal a component needed to stabilize his own version of the Omnitrix (the Stabilizer) to become an "Ultimate" Galvan. [S2E17] The Ultimate Heist
In this episode, the villain —a Galvan trapped in a human form similar to Ben's—orchestrates a plan to obtain a device that will restore his original form. The phrase "The Ultimate Heist" is also used
The phrase "The Ultimate Heist" is also used in other popular media and gaming, though typically not with that specific season/episode numbering: [S2E17] The Ultimate Heist
While the show is famous for its "Halloween Heist" episodes, fans sometimes refer to the grand finale or specific high-stakes heist episodes (like "The Last Day") using similar titles. "Ben 10: Omniverse" The Ultimate Heist (TV Episode 2013)
The reference to most commonly refers to an episode of the animated series Ben 10: Omniverse .