Get All Characters

Go to the main menu and press Up, Up, Down, Down, Left, Right, Left, Right, Y, Y, X. Now go to the options screen and save options

Increase Smackdown Meter

Press the taunt button rapidly during a match (this will leave you open to attack). Your meter will fill to its full level.

Real names

When creating a wrestler, you can make people such as Ric Flair, Hall, Nash and others and the announcer will actually say their names

Get Dory Funk

Beat career mode using Tony Funk

Get Jimmy Hart

Beat career mode using a Loved wrestler

Get King Kong Bundy

Use career mode to finish the Southeast territory

Get Robert Gibson

Beat tag tournament

Get Ricky Morton

Beat tag tournament

Get the Erichs

Beat career mode with Kevin Von Erich

Captain Lou Albano

Finish career mode with a wrestler in the "Hated"
category.

Ivan Koloff

Win the versus tournament.

Mr. Fuji

Win the Tag Belts in tournament mode.