Phineas and Ferb build a super computer so that they can find the perfect way to do something nice for their mom.
In the meantime, Dr. Doofenshmirtz searches for the key to his All-Purpose-inator, an invention that he believes to be extremely evil despite not knowing what it does.
* CaptainObvious: The super computer. It may have cryptic meanings, but the ending had it be this way.
* MadeOfExplodium: The super computer explodes upon hitting the Doofenshmirtz Evil Inc. building. This causes the roof of the building to explode shortly after. Twice.
-->'''Doofenshmirtz:''' [[LampshadeHanging Why does everything explode so easily?]]
* NoodleIncident: With the Tri-State area itself. With all the gladiator helmets Doofenshmirtz unearths, you'd expect that there was some sort of war fought there before.