The Phineas and Ferb Takeover Takedown Marathon is a marathon of almost every Phineas and Ferb episode, along with the TV movie Across the 2nd Dimension and several episodes of Take Two with Phineas and Ferb, that aired over Memorial Day weekend in 2018 on Disney XD. Starting at 5pm on Friday, May 25 and ending by 8:30pm on Monday, May 28, this marathon followed the I Know What We're Gonna Do In May marathon that ran during the first four weeks of May 2018 and appears to be a separate programming block, but whether it was or not was not made officially clear.
This marathon's schedule was similar to the Last Days of Summer Marathon, including the airing of Across the 2nd Dimension three times over three days, although it differed in the arrangement of a few episodes and the absence of "Phineas and Ferb Musical Cliptastic Countdown Hosted by Kelly Osbourne".