No combo pauses
Turn on the game, then immediately press [Left], [A], [B], [Up] when Pikachu smiles at the opening screen. A sound will confirm correct code entry. Skill chains and combos will no longer stop the blocks.
Turbo mode
Turn on the game, then immediately press [B], [A], [Left]x2 when Pikachu smiles at the opening screen. A sound will confirm correct code entry. The game speed in marathon mode may now be increased up to 99.
Intense mode
After completing normal mode with hatching at least one egg and having at least six Pokemon, go to challenge mode and start a new game. Highlight "Hard" at the difficulty selection screen, then hold [Select] and press [A]. The "S-Hard" difficulty selection will appear. Highlight it, then hold [Select] and press [A]. The "Intense" difficulty setting will be unlocked.
Bellossom
Play single-player challenge under the normal difficulty setting. Defeat any Gym Leader in less than 25 seconds before reaching Clair, to face a trainer named Lass. Defeat her to unlock Bellossom.
Igglybuff
To unlock Igglybuff, play the game for a while. You will obtain it without knowing it early on in the game, and you can use it in Marathons.
Marril
Play single-player challenge under the normal difficulty setting. Pull off a 4 block-combo before reaching Clair, to face a trainer named Swimmer. Defeat him to unlock Marril.
Pichu
Play single-player challenge under the normal difficulty setting. Stay undefeated for more than 4 minutes to face a trainer named Pokefan. Defeat him to unlock Pichu.
Sentret
Play single-player challenge under the normal difficulty setting. Pull off a 7-chain before reaching Clair, to face a trainer named Beauty. Defeat her to unlock Sentret.
Bellossom
Play single-player challenge under the normal difficulty setting. Defeat any trainer in under 25 seconds or less before reaching Clair to face a trainer named Lass. Defeat her to unlock Bellossom