How to unlock Big Heads
Press Down, Right, Up, Left, A, B, Y, X, White, Black, Start + Back at the title screen.

How to unlock 2D Players
Press Click Left Analog-stick, Left Analog-stick, Right Analog-stick, Right Analog-stick, press L, R, Black, White, B, A, Back + Start at the title screen.

Argentina Legends team
Win the American Cup with Argentina to unlock the Argentina Legends team.

Brazil Legends team
Win the American Cup with Brazil to unlock the Brazil Legends team.

England Legends team
Win the European Cup with England to unlock the England Legends team.

Holland Legends team
Win the European Cup with Holland to unlock the Holland Legends team.

African All-Stars team
Win the International Cup with an African team to unlock the African All-Stars team.

American All-Stars team
Win the International Cup with any American team to unlock the American All-Stars team.

Asian All-Stars team
Win the International Cup with any Asian team to unlock the Asian All-Stars team.

European All-Stars team
Win the International Cup with any European team to unlock the European All-Stars team.

World All-Stars team
Unlock all the other All-Stars teams, then win International Cup with any team to unlock the World All-Stars team.