Metroid II: Return of Samus

Metroid II: Return of Samus is best known as "that game between the first one and Super Metroid".

Debug Mode


GameShark code or Game Genie code  will enable some debugging features, all accessed from the pause screen.

Here you can adjust what items you have. Select a bit with Left / Right and press A to toggle the highlighted flag:
 * flag 0: Bombs
 * flag 1: High Jump Boots
 * flag 2: Screw Attack
 * flag 3: Space Jump
 * flag 4: Spring Ball
 * flag 5: Spider Ball
 * flag 6: Varia Suit
 * flag 7: Unknown

You can also change what weapon you're using by pressing Up / Down:
 * 00: Standard
 * 01: Ice Beam
 * 02: Wave Beam
 * 03: Spazer Beam
 * 04: Plasma Beam
 * 08: Missiles

With debug mode enabled, you can save anywhere! From the pause screen, press Select. As long as you're not in the air, your game will be saved. This causes the save text to be loaded over the enemy graphics when you start again, which can be fixed by moving to another area. You can also adjust the number of energy tanks you have by holding B and pressing Left or Right. (Removing tanks doesn't produce a visible effect until the game is resumed.) There is also an unused routine that would have saved the debug flag to the save file.