Zelda II stands out from the mainline series for emphasizing difficult combat-platforming, with little exploration; no other 2D Zelda is quite like it. And the puzzles or quests are often oblique. For that reason, Zelda II is often considered inferior or less of a Zelda game. However, removed from that context, Zelda II still manages to be a very fun and charming retro game that ended up being hugely influential in its era. It's tough, and you may need a guide, but it's worth the playthrough.