Complete Decathlon mode, scoring more than 8000 points. On returning to the title screen, hold X while selecting your game and player. In the JP release this will select the hidden athlete, Mankichi Kazami from the manga comic "Decathlon". Kazami was removed or disabled in the EU version, however if you check the sound test after trying the above, the last number in the test is no longer 166, Kazami's introduction and voice are available to listen to from 167 upwards.