Agent P Strikes Back is a game on the Phineas and Ferb The Movie: Across the 2nd Dimension website. The player must complete the three levels in order to complete the game. Agent P must free the other captured agents in the 2nd Dimension.
Unlike the movie game, which was a 3D platformer, this game is a 2D sidescroller. The goal of the game is to rescue three agents in each level and defeat Platyborg at the end of the level. Rescuing the agents is mandatory since they can open up locked passageways when freed.
Perry can also collect Platypus Tokens scattered throughout the level. There are two types: gold tokens add 100 points to the score and one point in the Token Counter, while platinum tokens add 500 points to the score and five points in the Token Counter. Collecting all 100 is entirely optional, but it helps to get a high score in the level.
The storyline follows Perry in Alternate Danville. Major Monogram informs Perry that Alternate Doofenshmirtz has captured nine of the agents from the O.W.C.A. Perry has to travel through three areas of Alternate Danville to rescue his fellow agents, avoiding the Normpatrol Robots scattered throughout the premises.
Once Perry reaches the end of a level, Platyborg stops him, and the two duel with Alternate Doofenshmirtz observing the fight. In the end, Perry defeats his alternate self and continues to the next area.
After defeating Platyborg a third time, Perry heads to Alternate Doofenshmirtz's lair, leaving a beaten Platyborg behind. However, after Perry left, Platyborg's robotic eye re-activates, signifying he's not fully defeated. The game ends with a message saying, "The End?".
- If the player hits the Norm Bot in the head, the Norm Patrol bot's helmet falls off revealing Norm's head.
- Fliers shows that 2nd Dimension Phineas, Ferb, and Candace are wanted for $10,000.
- Agent T makes an appearance.
- Agent P Strikes Back is most likely named after Star Wars: The Empire Strikes Back. Return of the Platypus may also be named after Star Wars: Return of the Jedi
- The agents that appeared all have dark brown fedoras like Perry but it should be that some agents should have light brown like Peter.
- Terry's skin in the game is green instead of orange.
- Sonic the Hedgehog 2 - In the boss levels, the Perry the Platyborg's moves resemble Silver Sonic's moves in the Death Egg zone.
- Kirby's Dream Land- Platyborg's fighting is also similar to Poppy Bros. Sr. (his jumping attack) and King Dedede (running around with a mace).