I've seen numerous eBay listings for the GameBoy Color Zelda games Oracle of Ages and Oracle of Seasons with varying photos. As far as I can tell, only the ones with clear, grey shells and a convex top are real and the other variations (including GBA versions) are reproduction cartridges, but I can't seem to find any corroborating information (lack of proof is not proof).
Can anyone confirm if this is the case?
(Sometimes the cartridges say "Game" instead of "GameBoy" in the concave area, but not always. Also, sometimes the listing mentions a replacement shell but authentic motherboard, while most of the time they mention nothing at all—even checking the model-numbers doesn't seem to help.)
Best Answer
After doing some research, there is no hard evidence that the game was specifcally released on separate cartridges for the Game Boy (GB), Game Boy Colour (GBC, and the Game Boy Advance (GBA), though I can provide some insight.
Firstly, the OOA and OOS games were produced for the GBC, with additionally functionality, should it be played on the GBA (emphasis mine):
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When we look at the design for the GBC cartridges, the transparent cartridge is designed specifically for the GBC (emphasis mine):
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Additionally, the colours of the GB cartridges refer to backwards compatibility - specifically, Black cartridges were GBC games that could be played on earlier GB models.
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The release date for the game, and with the "Special Features" if the game was played on the GBA would point to the validity of it being reproduced on the GBA, though there is no hard evidence for this, without speaking to the developers.