Hot Shots Tennis Cheats

Unlock God Difficulty Level
In exhibtion mode, beat the CPU at hard difficulty level a few times (the number is randomly set between 1 and 10). God Difficulty Level must be unlocked one by one for each character, in singles and doubles.

Unlock SP Costumes and accessories
In exhibition mode, beat the CPU at God difficulty level. SP items must be unlocked one by one for each character. Unlock Special Characters
Unlocking these characters requires coming back to a character's stage in Story Mode, once he or her joined the party, then talking to specific people.

Unlock Gloria: In story mode, after the second ending, go back to the volcano site and select to play as Suzuki before you enter the last room. Gloria will be inside
Unlock Norma: In story mode, after the first ending, go to the volcano site and beat every player until the final door. Play as Emi to enter, then beat Norma.
Unlock Suzuki: In story mode, once Schneider joined the party, come back to his stage then talk to Suzuki. He will challenge you, so beat him to unlock him.
Unlock Yakkun: In story mode, once Brad joined the party, come back to his stage and talk to Yakkun. He will challenge you, so beat him to unlock him.