30 lives, player two
At the title screen, press Up, Up, Down, Down, Left, Right, Left, Right, B, A, Select, Start.
30 lives, player one
At the title screen, press Up, Up, Down, Down, Left, Right, Left, Right, B, A, Start.
Continue playing
Quickly press Down, Up, B, A, B, A, B, A, B, A after you've lost your last ship.
Full power-up
While playing, pause then press Up, Up, Down, Down, Left, Right, Left, Right, B, A, Start.
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