Metroid Fusion Cheats

All Endings
Under 2 hours with 100% - Samus with suit off, standing up with a clear image of her to the left. Best Appearance
Under 2 hours, under 100% - Samus with suit off, leaning up a ledge with head leaned back.
Over 2 hours, 100% - Samus with suit off, in a city.
Over 2 hours, under 3 hours, under 100% - Samus with helmet off. Over 3 hours, under 100% - Nothing Special. Worst Appearance.

Secret Ending
Beat Metroid Fusion at 100% in under 2 hours to get the secret ending.

Samus without her suit
Successfully complete Metroid Fusion with a time under 6:30 and all items (100%) to see Samus Aran without the suit, wearing something similar to a bathing suit.

After Game Goodies
After you beat Metroid Fusion (no matter the time), go back to your game file WITHOUT TURING THE GAME OFF! when a menu pops up, select "Start Over". hence the opening movie, press start. you'll notice a timer in the bottom of the screen displaying elapsed time of Metroid Fusion and counters of Missile Tank Updgrades, Energy Tank Upgrades and Power Bomb Upgrades. also in that sector you are in, on the map in the Metroid Fusion start menu, it will show you if you have collected all the items in that sector.