At the screen with Japanese text that appears after the Genki logo, hold L + R + A.
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Game Shark Codes
No Strikes Recorded (Press C-Left)
D02CD565 0002
8037919C 0000
No Outs Recorded (Press C-Right)
D02CD565 0002
8037919E 0000
P1 Score Modifier
80379192 00??
P2 Score Modifier
80379193 00??
