This is a sweet cheat

Special items- Stand on the mushroom to face the scientist when first meeting him. Quickly press (R)x2, (Analog-stick Up), (Analog-stick Down), [Up], [Down], (C-Up), (C-Down), (C-Left), (C-Right), (C-Up)x2, (C-Left)x2, (C-Right)x2, (C-Up)x2, (C-Down)x2, (Analog-stick Up), (Analog-stick Down), (Analog-stick Left), (Analog-stick Right), (Start) to receive all special items.