I'm not sure but I think they may be the secret ***SPOILER ALERT!!*** messages from the developers of the game.
no there isn't any cheat codes,but there is unlockables
Here are the different planets that you have to go to to beat prime 3: GFS Olympus(Space ship, not a planet), the GFS Valhalla( another ship. you have to go through this level to get access codes to a leviathan ship), Norion, Bryo, Elysia, the Space Pirate Homeworld, and finally, the Phazon planet Phaaze. In Phaze, you will go through the level and fight Dark Samus, and a few stages of the Aurora unit.
http://www.cheatscodesguides.com/gameboy-advance-cheats/metroid-zero-mission/
Yes, if you have the right codes for the game and the region. I have previously used codes on the Super Metroid Phazon Hack and the hack for Metroid Zero Mission.
Yes, the gameshark can work for tons of games, you just need to have the codes for it.
yes.metroid prime hunters have action replay codes.
aliens- astros- drill not theylive
The code for alien special operation levels are: 11 12 and 13 for the aliens.
you can but you have to get the right codes for it like camochao's in freewebs.com
Yes. You have to buy an Action Replay for GC though which may be hard to come across in regular game stores.
There is a diag port on the panel below the steering column. Any OBDII reader can get the generic codes, but the special VW codes can only be read with a VAS5052 or VAG-COM software.
Special edition roar codes or codes to help you on the game roar on the cbbc website.