Zelda II: The Adventure of Link is often considered the worst game in the history of The Legend of Zelda. It's not difficult to understand why, considering it's a break from the familiar mold that made Zelda popular in the first place. Nintendo abandoned the attributes from the 1st Zelda game, and turned Zelda II into a RPG, and that didn't turn out too well.
Zelda II doesn't play like a normal Zelda game. The most notable difference is that it's side-scrolling. If you're a fan of the top-down approach in various Zelda games, you may find this a little hard to get used to. The game also requires you to engage in countless battles simply to level up, which is a common RPG element, but not entirely suitable for a Zelda game. It adds to the length of the game, but Zelda to me is always more about solving puzzles than building up Link's powers. Some of these battles are also very tough, and many times, they are also forced. But hey, no one say waking Zelda from her slumber is an easy job. In any case, you need them to level up, so it could be quite a long and tedious prospect getting Link to be ready for stronger opponents.
Fans of the additional weapons that are so popular in the Zelda series, like the boomerang and arrows, will also find the sword/ shield combination in Zelda II a little disappointing. Yes, you've no other weapons throughout the game, and yes, it bothers me after a few minutes. To improve Link's attacks, magical spells are included instead. You need learn these magics, and collect magic points to make them work though, and the range is pretty impressive. Link can improve his shield's defensive power, jump higher and even cast a spell to unlock a blocked path with these magic points. While they are fun while they last, somehow they fall flat on hindsight. Give me a boomerang anyday.
Graphics and audios are basic 1980s stuff. I'm inclined to be more forgiving when it comes to these, since it'd be unfair to compare them with modern standards. The screen fits well into a GBA, and doesn't appear as cramped as The Legend of Zelda. The music is quite soothing, but it's still more or less a remix of the classic Zelda tune, with some extensions. The fact that it mirrors the original game is good enough for me. At $20 a pop, however, the game is perhaps a tad overpriced.
Overall, Zelda II on the GBA is an ok game, but fans may find more fun in other titles from the series. This is a good try from Nintendo to offer something different from its first instalment, but it just fell short of being a truly great Zelda game.