This is something I ran across years ago from GameStop and still have in my collection. The cartridge is the solid gray kind, has the word "Game" atop instead of "Game Boy", and the cover art used is clearly from the game's box art, to the point the boxes next to the "play both for the ultimate adventure" text are cut off by the borders. The borders themselves do retain the usual game boy box layout and the cart's serial number. The cartridge itself says "Pat Pend" on the back with no additional markings, and nothing showing it to be a Nintendo cart other than its looks.
To boot, it still works and is entirely just OoA. No other games crammed in, no bitrot.
Has anyone else run across anything like this?
EDIT: And of course after posting this I run across the answer through Google image search: http://www.nintendoage.com/forum/mes...threadid=15146 To be completely honest a part of me always wondered if there was a matching "Boy" cartridge of Oracle of Seasons out there. Guess not.