International Superstar Soccer '98 cheats and cheat codes for Nintendo 64

Go to the title screen. While the "Press Start" text flashes 
press the following button combination:
Note: If the codes are accepted you should hear a sound.

Giant heads
Press C-Down, C-Down, C-Up, C-Up, C-Right, C-Left, C-Right, C-Left, 
B, A. Then hold Z and hit Start.

Unlock World Stars team
Press Left, C-Left, Right, C-Right, Left, C-Left, Right, C-Right, 
Down, C-Down, Down, C-Down, Up, C-Up, Up, C-Up, B, A. Then hold Z 
and hit Start.

Unlock 5 bonus teams:
Press Up, C-Up, Up, C-Up, Down, C-Down, Down, C-Down, Left, C-Left, 
Right, C-Right, Left, C-Left, Right, C-Right, B, A. 
After hold Z and hit Start. Now you can select African Stars, 
Asian Stars, Euro Stars A, Euro Stars B or All American Stars.

Various player tricks:
During game play, hold C-Left.

Unlock 5 bonus teams:
Play on difficulty level: 4 or higher and win 1st place in the 
league championship, after beat the World Stars team. 

Change head views
Go to the player creation menu then, hold C-Up and hit Z, L, 
or R and the face will turn around. 

More heads
Play on difficulty level: 4 or higher and win 1st place in the
International Cup. After go to the player creation menu 
after the ending movie. Go to head selection menu and hit L.
You can find different strange heads that may be used for 
your player.