While the debate over goes on over whether or not Nintendo's Zelda II: The Adventure of Link for the Nintendo Entertainment System is a proper part of the franchise, most of the compliments and criticism towards the game refer to the North American version of the adventure that was released as a game pak in late 1988. Most folks missed the early 1987 Japanese version of the game for the Famicom Disk System which features its own quirks. While Nintendo required nearly two years to localize the game and produce cartridges for the international audience, the company also used the time to make several changes to the game's aesthetics, bosses, and sound effects (among other things). Check out this seven minute comparison video from YouTube and see the differences between versions for yourself.
The Adventure of Link was originally released on the Famicom Disk System before its worldwide release. Like its predecessor, the FDS version appears to be an earlier version of the game, with a few obvious differences. In the English release, the dungeons each have different colors, whereas in the FDS version they are all gray. Also, the two dungeon bosses Carock and Volvagia (the latter being initially named Barba in the NES release) have different graphical appearances. The game over screen in the English version features the silhouette of Ganon from the chest up, with the text saying "Game Over - Return of Ganon", whereas the FDS game over screen is a plain black screen with the text saying "Return of Gannon - The End". There are some slight additions to the dungeons, as well as a handful of differences on the dungeons themselves. Due to an additional soundchip that the Famicom Disk System had, when Nintendo ported Zelda II over to the NES they had to eliminate some musical elements, especially from the title screen. On the main map, the icons denoting attacking monsters look different, but the most significant change is the spending of experience points, as Link's three attributes cost the same, unlike the worldwide release. This makes leveling up in the game very different.
Don't cry for the Japanese audience, however. When the game has been re-released in recent years for modern Nintendo systems and services, the international version of the game with its many added colors and bosses is the version offered up (albeit with additional little tweaks, but nothing as major as the ones seen here). Once again we see that the first release of a game is not always the best and that publishers have been releasing slightly unfinished games for the sake of meeting a deadline for quite a long time.