Well, all of it. It's the combination of all of these that has made Zelda into what it is. If one of these was particularly weak compared to the rest, it would be a poor Zelda game.
Memorable music + likeable NPCs + overworld secrets = Zelda
At least that's the formula for me. I think that's why I'm so fond of Wind Waker. Each island holds a secret for you to unlock, with some islands containing multiple secrets. The music is probably my favorite as far as Zelda music goes. And the NPCs are great, especially on Windfall Island which is just a smaller and less complex version of Clocktown from Majora's Mask.
Memorable music + likeable NPCs + overworld secrets = Zelda
At least that's the formula for me. I think that's why I'm so fond of Wind Waker. Each island holds a secret for you to unlock, with some islands containing multiple secrets. The music is probably my favorite as far as Zelda music goes. And the NPCs are great, especially on Windfall Island which is just a smaller and less complex version of Clocktown from Majora's Mask.
KA-BOOM!!!!
Sploosh!!!!!!
People like that NPC? God that guy gave me nightmares. Plus I thought he was a pedophile at one point. I mean I think he has a cut out picture of Tetra or some little girl. Then he roled played as it. *Shivers*
Really though I agree with what he said, but with Majora's Mask because I can't remember a single tune from Wind Waker... or a single NPC that I liked... and the game was bare in the way of secrets because it had a lot of empty tiles on the map... Anyway my point is, it needs to have all of that. Plus a good story. I mean I play games mostly for story, which Zelda is also somewhat plot driven.
When a person buys a game in general, they think of questions like "Is this worth its cost?" "Will this be time consuming enough for me?" "Will this enhance my experience as a gamer?" And so on. The Legend of Zelda series gives opportunities that involve long playthroughs, very many secrets, mind-boggling puzzles, and a completion effort towards all of its gaming experience. Also, much like many great games, it has amazing graphics and a good look to it, along with a unique and memorable soundtrack.