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.
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!!Tropes present:
* 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.
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