Super Soccer Cheats
Play as Team Nintendo
Select two-player mode. Hold Start + B on controller two at the team selection screen. Player two will control Team Nintendo. (An alternate version of the code is to press A, B, Select, Start at the team selection screen.)
Play against Argentina in finals
Press Up, Down/Left, Right(3), Up/Right, Down, Up at the team selection screen.
Select the "Continue" option on the tournament mode screen. Press Up/Right, Down/Left, Right, Down, Down/Right, Left, Down/Left, Up/Right. An "Expert" option will now appear on the main menu.
Wait for the referee to take the trophy after beating Argentina in the finals. A bonus game will begin.
Same country vs. same country
Select two-player mode. Highlight player two's team, then hold Start + B on controller two. This will change the selection to Team Nintendo. Highlight the same team with player one's controller and press Y on controller two. Team Nintendo will revert to the original country selected. Both teams will now be from the same country.
No red cards
Hold L + R when the referee issues your team a red card. The tackled player will receive a red card, while issuing yellow card to your team.