- The baby heads return, but there is an entire dimension full of them.
- The Goozim monster was a bit frightening. And it's implied that it wasn't the first time Doofenshmirtz-2 tried executing someone with it. Speaking of the monster, remember what shape it turned into after it jumped into the portal after Phineas and co.? Most of its body was shaved off, including its limbs.
- A few of the dimensions during the "Brand New Reality" sequence, even if they only flash by for a second, are rather unsettling. Especially the last one, which dips into Uncanny Valley. *shudder*
- Doof-2. He rules parallel Danville with an iron fist as a dictator, with an army of Mecha-Mooks (thankfully some relief given that they are based off of Norm) led by a familiar platypus that you now see has turned evil against his own will. He forces everyone to conform, as well.
- Even his wife Charlene-2 counts as one in the episode sequel, as she led an army of animal cyborgs (similar to several animal agents from the original dimension) during her husband's reign, as they have all turned evil against their will.
- The fact that this might have been OUR Doof, had his childhood transpired differently. For whatever reason, a very minute difference between the two was the only real change (Doof-2 lost a beloved toy train as a child while Doof-1 never did) despite all the horrific abuse and neglect Doof-1 suffered and Doof-2 didn't. Doof-1 might have been far worse had this one loss made him snap.
- The robot dog Phineas rides during the Robot Riot scene, named Rover in another episode, may look a quite a bit disturbing from certain angles.
- Then again, so does Phineas
- The final battle. With Perry distracted with Platyborg, no Ferb to pull a failsafe out of his pocket and no gadgets to aid him, Phineas is totally alone against a towering madman who wants to kill him.
- Or turn him, as Doof-2 puts it, into a "boyborg".
Nightmare Fuel / Phineas and Ferb the Movie: Across the 2nd Dimension