Most of the time the cartridge is a different but ya never know,
a way you could tell is put it in your gameboy,and if you start to see stuff different like the texts at the bottom of the screen,then it's fake.
Like this.
Regular:
the regular way it would load be Intro,Press start,Choose which of the 4 and or (Example:Continue
Player Absol Time 54:48
Pokedex 14 Badges 8
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| New Game |
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|Option |
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Fake:Example:
Text:The game has been updated,Your game will now be loaded.
OR... everything in the game the colors will seen faded.)