The Legend of Zelda featured a nonlinear open world with 8 dungeons. Ganon, wielder of the Triforce of Power, wants to complete his golden triangle collection, so Zelda split the Triforce of Wisdom into 8 pieces and hid them from Ganon in these dungeons. Link collects them, goes to Ganon's Lair, and kills him. No, seriously, Ganon is killed off in the first game.
The game introduces the three main characters, the setting, and two of the Triforce pieces.
Adventure of Link's backstory is pretty neat. Long ago, an unnamed prince of Hyrule was angry that he did not inherit the Triforce when the king died. An evil unnamed wizard told him that his sister, Princess Zelda, knew where the Triforce of Courage was hidden. When she told him nothing, the prince had the wizard cast her into a magical sleep. Afterwards, he repented, but only the Triforce can break the spell, so there's nothing he can do to help her. In her honor, he orders that every princess of Hyrule will be named "Zelda". Fortunately for the first Princess Zelda, the spell also kept her alive. Link goes to collect the Triforce to wake her up. Ganon's minions know a spell to bring him back, but they need Link's blood, so they're constantly trying to kill him. Ganon isn't actually in the game, he's just the game over screen. This is actually a sidescroller. It introduces the Zelda lineage (although Skyward Sword reveals it dates back longer than Hyrule itself. She's just not a princess in Skyloft) and the third Triforce piece.
A Link to the Past, the next "normal" game in the series, introduces the standard structure, sometimes called "The Legend". You get three mcguffins, obtain the Master Sword (in its first appearance), go do...[sub]stuff[/sub], and then fight Ganon. I don't really think this should count as a formula for two reasons. First of all, it was only used in three other games. Secondly, the part between getting the Master Sword and defeating Ganon is incredibly vague. How many post-Master Sword dungeons Link needs to clear, when Zelda is imprisoned, when she's rescued, and how much help she provides is inconsistent. Since "The Legend" is kind of vague at the end and only happens in four of the fourteen (soon to be fifteen) games, I don't really think it's strict enough to be a formula. It's more like...a guideline. Anyway, ALTTP also introduces the Sacred/Golden Land (which Ganon has corrupted into Dark World), another part of Hyrule's backstory (there was a civil war for the Triforce, the king had the sages/wise men seal off the Sacred Realm/Golden Land so no one could get it) and the concept of Ganon stealing the spotlight from another villain for the climax (which he does again in Oracles, Four Swords Adventure, and Twilight Princess).
Ocarina of Time, originally conceived as a prequel to A Link to the Past (but these days, who knows what order they go in?) was the first game to follow A Link to the Past's structure...get the spiritual stones, obtain the master sword. Basically, if it's still the prequel, then the ending explains how Ganon got into the Sacred Realm/Golden Land/Dark World. Zelda takes a semi-active role in this one (for the first time). It's the first game they show Ganon in his human form, and it introduces Hyrule's creation story and several other cultures (The Gerudo and Goron are new here...I think. The Zora aren't new, but this it the first time we got to see their city).
Majora's Mask is the direct sequel to Ocarina. The Triforce, Ganon, and the Master Sword are nowhere to be seen, and Zelda just gets a flashback cameo. Link is stuck in a time loop and has to stop a skull kid wearing an evil mask from pulling the moon into an Termina, an alternate universe equivalent of Hyrule. It's populated by Gorons, Zora, Gerudo, and Hylian Clones, but it is almost nothing like Hyrule culturally. (Well, the Gorons and Gerudo are similar to their Hyrule counterparts). Link accomplishes his goal by using magical masks that he gets from dead people to shapeshift into them. Yeah, this one is kind of creepy, and despite re-using almost everything from Ocarina, is the runner up for most unique game in the franchise from a gameplay perspective, and definitely the most unique in story.
The Wind Waker takes place in a happy post-apocalypse Hyrule. It begins by recapping the backstory of A Link to the Past and the events of Ocarina of Time (somewhat incorrectly...it's a legend in their world now, so it's been distorted a bit. It could have easily merged with some tales, and others could have been forgotten. This is why the timeline discussion is a little fuzzy...if the people in that world can't keep track of it, how can we?) Anyway, Ganon came back, and Link wasn't there, so the gods flood Hyrule to keep him away from the Triforce. A century-or-so later, Zelda, who's captain of a pirate ship and is actually named Tetra, takes a direct role in helping you throughout your quest to save Link's sister, and, afterwards, on you quest to kill Ganon. Ganon actually gets some much-needed development in this one, but his plan hasn't changed much. Like Ocarina, Ganon kidnaps Tetra near the end to obtain the Triforce of Wisdom. Unlike Ocarina, she is rescued before the battle with Ganon, picks up the light arrows, and helps you kill him. Again. Its story is similar to Ocarina of Time and A Link to the Past, but it concludes that story arc. Old Hyrule, Ganon, the Master Sword, and the Triforce are gone, and it looks like it's for good this time, 'cause the handheld sequels (Phantom Hourglass and Spirit Tracks) seem to be moving the story along.
I haven't played Four Swords Adventure, so I can't go into as much detail here. Basically, it's where the Four Sword arc from the handhelds melds with the Ganon-wants-to-conquer-Hyrule arc from the consoles. Also, it appears to be the backstory for Ganon (Maybe. It talks about him finding the Trident that he uses in older games) and Shadow Link. As far as I know, he's trying to conquer the good old fashioned way and the Triforce doesn't even make an appearance (which adds to the backstory possibility, if Ganon doesn't know about it yet). If I understand it correctly, Vaati (the villain from Minish Cap and the Four Swords) is killed off in this one. So this one gets rid of one villain and possibly explaining the roots of two others. Maybe.
[sub]Disclaimer: If any time line theorists are reading this, I repeat, I have not played this one. I got my summary from a quick read at tvtropes. I know this is a particularly debated game when it comes to its place in the timeline. I won't have a final conclusion until I play it myself; I'm only reporting what I read. [/sub]
Twilight Princess is basically the reason that the split-timeline theory exists. Well, actually, that's not quite right...the split timeline exists because Aonuma says so, but Twilight Princess is the only time it's
needed. It's a post Ocarina of Time Zelda game that contradicts A Link to the Past's backstory (Ganon is sealed into the Twilight Realm instead of the Sacred Realm/Golden Land/Dark World) and, if it weren't for the split timeline, would do the same for Ocarina's ending (He's sealed away before he can conquer the kingdom, and, again, in a different dimension). It's the only game that is pretty much impossible to fit well into a single timeline. In addition to practically confirming that there's two timelines, it also expands on that war from A Link to the Past's backstory. A tribe tried to capture the Triforce using their dark magic. They were banished into the Twilight Realm for this. (They are speculated to be Gerudo, who are absent from the game). Their weapon, the Fused Shadow, is an important plot device for the game. Most of the plot deals with Zant, king of the Twilight Realm, invading and conquering Hyrule. Zelda (who's only still a princess because a demonic invasion is slightly more important than a coronation) isn't even kidnapped; she's under house arrest in her own damn castle, which is why she isn't quite as active as Tetra. Ganon becomes a footnote in the story about halfway through, and he isn't active until the final dungeon. He does have the exact same motivation as A Link to the Past and Ocarina of Time here, but that was done on purpose. Twilight Princess is
suppose to be like Ocarina of Time. Skyward Sword is apparently going to radically change the series again, just like Ocarina of Time did so many years ago, and both Nintendo and its fans wanted one more game like it before the next era began. Personally, I thought Zant's part of the story was more interesting, but I get their reasoning behind the finale. The Wind Waker was the conclusion of Ocarina's story arc in-universe (in the Adult timeline anyway

), but Twilight Princess was the conclusion in spirit.
Yes, The Wind Waker and Twilight Princess have similarities to Ocarina of Time and A Link to the Past. However, both are conclusions of that story arc (one literally, one spiritually), and the differences are not just superficial. Both the obvious changes (flood and pirates, wolf and demon army) and the partners' subplots are much more than superficial changes, and each console game expands the universe--either by elaborating on the backstory (expect to see a lot of that in Skyward Sword), or by moving the story forward drastically, like Wind Waker.
I already discussed why I didn't think "the Legend" held up as a formula, but I'd like to elaborate on Ganon's part. I see the similarity in Ganon's plans as a character flaw, not a writing flaw. The Triforce isn't just part of Link, Zelda, and Ganon's backstories, it's the core of their characters. Link is courage incarnate. He doesn't care what's in his way, or even if it's his world that is in trouble, he will save the day. He will accept all calls to heroism. Zelda's wisdom allows her to be a good leader, whether it's knowing when to surrender to a demonic invasion in Twilight Princess, planning ahead to stop Ganon in the first game, or simply being a good captain in The Wind Waker. Likewise, Ganon is defined by his power. He plans like a warrior. He'll defeat Zelda and take the Triforce of Wisdom, then he'll defeat Link and take the Triforce of Courage. The details change, his approach changes a little, but that is the core of his plan because power is the core of his character. When you look at it from his perspective, they aren't bad plans either, especially considering he consistently comes closer to victory than any other recurring video game villain I can think of.
Where many see a cliched formula, I see a persistent villain and a constantly expanding continuity. So, yes, I can say it's more than superficial changes.
Also, I hope you enjoyed the read. I went into a
lot more detail than I originally planned.
