Adventure Island IV is a Famicom exclusive video game (i.e.: It was never released in America nor Europe on the NES). It is known as the last official video game ever to be released on the console - almost four years after the Super Famicom was initially released and 11 years after the Famicom was released.
The game, while still a side-scroller, is wildly different from the three previous games that were released on the console. It is more inline with games such as Metroid, as it's less of a platformer and more of an action-adventure video game. The next game in the series, Super Adventure Island II, was very similar to this title. Currently, English speaking fans of the series can play the game via a translated patch.