Gunhed

Avoid and do not shoot the Boss at the end of any odd numbered level. After the Boss leaves, 16 lives, 36 bombs, and a double score will be awarded.

Don't shoot any bosses who are on odd numbered levels (1,3,5 etc). You will receive the lives, bombs and score when the boss leaves.

Hold Select, press Run at the title screen, and wait until the phrase "Area 1" appears.

Enable Sound Test cheat. Press I, II, than keep pressing Select until the debug screen appears. You can now do the following:

Enable the "Sound test" code. Press I, II then tap Select repeatedly until the debug screen appears. The following debug functions may now be enabled.

Level select
Enter 00 - 09 as a debug number.

Invincibility
Enter 77 as a debug number, then press Up, Down before exiting the debug screen.

Half game with many satellites
Enter 83 as a debug number.

Extra lives, bombs, and power
Enter the debug number for the desired level. Hold I + II and press Start to begin game play with 10 lives and 10 bombs. Additionally, you will continue from the previous location instead of the previous checkpoint after losing a life.

Hold Select while tapping I, II repeatedly at the title screen. Press Select to choose between four difficulty levels. Begin game play by holding Run and press Select. Alternatively, enable the Turbo switches and press I + II to start the first part of the code.

After selecting your mode, press Run and Select simultaneously to reset the game.

Hold Select and alternately press Left and Right repeatedly until 'Sound 01' appears.

Hold Select and alternately tap Left, Right repeatedly until "Sound 01" appears.

Enable the "30 continues" code. When the current game ends with 30 continues remaining, press Select, Select, then hold Select + Run until the game restarts.