Puyo Puyo Sun 64 (N64)

Reversed character select:
Highlight Draco (the training character, far left in the front row) and hold Start. Player one will be able to choose player two's character and vice versa.

Play as Carbunkle:
Highlight Arle (the main girl character, second from left in the front row) and hold Start until Carbunkle appears.

Play as Satan:
Highlight Shin (the character to right of Arle) and hold Start until the Satan appears.

All characters are elephants:
Highlight the elephant (far left in the back row) and hold Start.

Random character select:
Highlight Lulu (far right in the front row) and hold Start.