The reference to most commonly refers to an episode of the animated series Ben 10: Omniverse .
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) [S2E17] The Ultimate Heist
He seeks to steal a component needed to stabilize his own version of the Omnitrix (the Stabilizer) to become an "Ultimate" Galvan. The reference to most commonly refers to an