Dragon Fighter

Level Select
Hold the A + B buttons on the first controller and press Reset, continue holding the A + B buttons on the title screen for the next 30 seconds. A sound will notice you that the cheat is enabled and you can release the buttons. Before the demo sequence start, you can hold one of the following buttons on the second controller to select desired level and then press Start on the first controller.

Sound Test Mode
At the title screen, when message "PUSH START" appears, hold A + B then press Start. The "SOUND TEST MODE" screen will appear. Unlike most of other sound tests, this one refer music compositions by it's own names, given by composer. Press Up / Down to select music, press A / B to start or stop music accordingly.

Here is the complete music list:

Object Test Mode
The Game Genie codes (for the Japanese version) or  (for the US version) replace the "SOUND TEST MODE" screen with the "OBJ TEST MODE" screen. Press Up / Down to change displayed object, hold A then press Up / Down to change CHR data bank.

On the early development stage, there were another cheat handling routine. The level select enabling cheat was actually the global cheat enable trigger. In addition to the level select you were able to select "OBJ TEST MODE" by pressing B + Select + Start on the first controller, and "SOUND TEST MODE" by pressing A + Select + Start on the same controller. In the final release "OBJ TEST MODE" was disabled and "SOUND TEST MODE" was moved to a simplier cheat combination.

The old cheat routine still can be re-enabled in the Japanese version, since the code is still there, but can't be restored in the US version, where it was completely removed.

CPU Usage Meter
The Game Genie code re-enables the development stage routine in both regional versions. To use it you must enable the Stage Select code first, then during game press Select to change the power mode (Green, Red or Blue), also you can see the CPU usage meter as gray line floating on the screen. Some unknown function can be enabled by press A on controller 2. Only visible effect for this is a unrevertable game pause. There is a lot of code, but meaning of it isn't clear.