Press Right, Select, Right, Select, Right, Select at the title screen. The word "Credit" will appear under "Blaster Scramble 2" to confirm correct code entry. Press Up and Down to get up to nine continues for game play. The following cheat functions may also be activated.
Difficulty select
Press Up/Left, Down/Right and repeatedly tap Select until the screen turns blue (easy difficulty) or yellow (hard difficulty).
Level select
Press I(10) to select level two. Press I for each additional level to be selected. Press Select(2), Run to begin game play at the desired level.