The Game Genie code XTVYGGAV activates a Stage Select. There's two different "sets" of places to go; One that starts you off in a particular world with the tank, and the other starts you off right before the boss.
In the Japanese version (Metafight), the Stage Select itself works fine (but you need the code EKNYUYAA to use it), but in the U.S. version, some things were altered so it turned into more of a demo viewer than anything, unfortunately.
The Game Genie code GAUGIKGK enables a couple of minor debug features in the game.
- Pressing "Up" on Controller 2 freezes the game on a black screen. Probably linked directly to development tools.
- In the Top-Down screen, your gun points will instantly be maxed out.
- If at any time you run low on Gun Power, pressing "B" on Controller 2 will refill the Gun Power meter.