Is there a specific code to get bad egg on Pokemon firered?

Yes, there is a code to get bad egg in Pokemon firered using a cheat device like Action Replay or equivalent code devices.

Action Replay

Master Code

94000130 FCFF0000

Egg Code

C2017A8D 2DDFDD89

To do so:

- Enable the `Master Code`

- Insert the `Egg Code`

- Fly to any city using Fly HM on your Pokemon

- Move to the Pokemon Day Care Center located in the south-east of any town

- Deposit any Pokemon in the left slot of the Daycare center with a Ditto on the right slot.

- Wait few seconds and run out of the building

- Re-enter the Daycare and grab the Pokemon on the left.

The Pokemon in the left slot should now be a bad egg.