Not as useless as in DDD.
Now, when you play KH2 the first time, you might think that at that moment, Maleficent is officially just a second-rate side villain since she decides to waste time turning Santa into a heartless when she should instead try to conquer the universe. However when you really think about the whole grand design of her campy plan, you realizes that it might be one of her most sadistic and sick plans ever. Santa Claus whole job is to deliver Christmas presents to nice boys and girls at Christmas, and from what we can hint from his first scene with the list, he dont just move around in his own world but to other worlds as well, just like the heroes but with a sled instead of a gummi ship. If he were to turn into a heartless, he still would be able to travel around the worlds to all nice boys and girls during Christmas, but instead of presents as gifts for their niceness, they would get a Santa Heartless who would take their hearts and turn them into Heartless as well their family members. So what Maleficent is doing is not Villain Decay since she plans to boost her Heartless horde by turning a beloved and popular figure into a monster and then let him loose on innocent, goodhearted people, specifically children, from around the universe, and no one would see it coming, since Santa is the last person they would suspect being an heart consuming monster acting on orders of one of the most megalomaniacal people around.
We can probably expect this critter to show up in KH3. I'm still perplexed why Emblem Heartless appear in that game, though...
I'm of the impression that the emblem heartless existed long before Xehanort's ambitions and that it has something to do with the sixth keyblade faction.
Neat, maybe that will be in KH3? Chi was that browsers game right? Don't tell me it's tied to the KH story...
Yeah, but really, really loosely. I wouldn't worry about it.
I would. On top of that, I think that there's a chance of BBSV2 still coming out to fill in some of the back story, much in the same way that Days was used to fill in story gaps. BBSV2 could elaborate on Aqua's time in Darkness, what Mickey and Riku were doing between KH1 and KH2, and set up the new villain for KH4. Plus, the foreteller's script indicates vaguely that Xehanort will succeed in his ambitions, which works simply because his goals do not preclude his destruction. Imagine if Xehanort forges the χ-blade and unlocks Kingdom Hearts, but then is still destroyed by Sora and co. You have to keep in mind that Xehanort's goal isn't ruling the universe or coating the worlds in darkness: he's a mad scientist. He only wants to see what happens next.
If Oswald shows up in KH3, he should be a Superboss. There's been a lack of Disney themed Superbosses (just Ice Titan in the first game and Julius in 3D, and I guess Rock Titan in the first if you want to get technical).
I think with the sheer breadth of story needed to cover in KH3, Oswald should be left out. Mickey and Oswald would make an excellent plot thread for a sequel (perhaps the aforementioned BBSV2) and I would hate to have them throw him away for a simple boss battle.
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I raised this question on reddit and I would ask the same of neogaf:
How should KH3 handle multiple player characters?
(I'm not referring to multiplayer. I'm referring to multiple protagonists a la Birth by Sleep and 3D.)
Considering again the breadth of story needed to cover in the final chapter of the Xehanort Saga, I think it would be wise for KH3 to not load all of the story onto poor Sora's shoulders. Plus considering KH2, BBS, Days, and 3D all had multiple playable characters at one point or the other, it's not all that big a stretch to assume that KH3 will as well.
So the question is how then should the multiple characters problem be tackled?
We can tell from the iterative design* of Kingdom Hearts games that they are planning some solution to this.
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Concept 1: Birth by Sleep - You have multiple characters each with their own independent save file with an interwoven narrative and upon completion of all of them, unlock a final story.
Pros: Very simple and straight forward.
Cons: Kind of a pain in the ass juggling saves. Going through the same worlds over and over.
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Concept 2: Dream Drop Distance - You have the characters swap at predetermined intervals. May or may not be in the middle of battle.
Pros: Single save plus the best implementation of narrative integration.
Cons: Going through the same worlds over and over. Drop during a boss fight. I don't think I need to say more.
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Concept 3: 358/2 Days a la GTAV - You choose who you want to play when you want to play them with some restrictions.
Pros: You get to play as who you want, when you want. (My name is Master Aqua. Now return my friend's heart or pay the price!)
Cons: It would be a hell of a lot of work to make different scenarios for each choice, meaning they would prolly just do the same dialogue and such regardless of who you play as which would be totally lame.
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Concept 4: Divergent paths (not seen in series before) - Basically, while Aqua's in Kauaʻi with Stitch, Riku is helping Kuzco with Kuzcotopia, and Sora is helping Taran and Eilonwy in Prydain. Can be used in conjunction with the previous concepts.
Pros: It would make playing as each character more refreshing, as you wouldn't be retreading ground.
Cons: It would either be a ton of work to design a number of non overlapping worlds for each player character or each character would only get a handful of worlds in which to play. Plus there's the all too real possiblity that each character only get one or two worlds and the rest be overlapped.
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Concept 5: Reverse/Rebirth - You play the entirety of KH3 as Sora and upon completion, you unlock the ability to play as Riku. Beat it again for Aqua, ect ect.
Pros: Twice the game for your buck!
Cons: The internet would immediately spoil the surprise, especially if KH3 doesn't do any all regions release. Plus, there's a very real possibility of fatigue setting in. I mean, I still haven't finished RE:CoM's RR mode, simply because it's the sixth time I'm playing the damn thing (GBA CoM, GBA RR, KH2FM+ CoM, KH2FM+ RR, RE:CoM English, RE:RR English...). And now with ReMix... but I digress.
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Concept 6: Party System a la FFXIII - suggested by scarymonkey11622
Instead of having to pick through seven characters, there would be three main groups. Sora Donald and Goofy, Riku Kairi and Lea, Ven Aqua and King Mickey. Sora Donald and Goofy would traverse through worlds in the realm of light (Disney worlds), Aqua Ven and Mickey would investigate places like the realm of darkness and worlds in between, and Riku would be training Kairi and Lea (different Disney worlds).
Everyone has their own set of skills and worlds that they can explore. Once you reach a certain point in the story, all the other worlds will be unlocked. For example, Soras party won't have the ability to go to Castle Oblivion like Mickey's party. But once those two party's meet, Sora now has the ability to go there. This brings back the platforming element to Kingdom Hearts that was lost in DDD. For instance, only Sora can use glide, only Aqua can double jump, and only Riku can manipulate darkness to find certain areas otherwise inaccessible.
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Concept 7: a mixture suggested by TlMB0
You'd start off the game with Sora, Riku, Mickey, Donald, and Goofy as available party members. You can roam Yen Sid and can now be put in your party. Aqua is freed from the Realm of Darkness and she joins the crew. Ven comes soon after that, and Terra finally (likely near the end of the game?).
Whilst exploring the worlds, doing side quests, and just doing whatever you want, you can choose to use any party you'd like. But mainline story missions and certain side missions would require either specific parties, or a specific character in your party. For example, you'd have to have a part consisting of Riku, Mickey, and one other member while searching for Aqua in the Realm of Darkness. You must have Aqua as the party leader while working your way to find Ven's body in Castle Oblivion. You must play as Lea for the mission that involves taking out Isa. You must play as Sora, Donald, and Goofy for the final battle. That kind of thing.
Most of the mainline missions require Sora, as this is definitely his story over all, but it also gives the other characters each their own moments in the spotlight and allows for you to play as whoever you'd like to while you are just messing around.
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Concept 8: You tell me. If there are any that I missed/a game that did multiple protagonists well that I failed to mention, please share.
*for example, we can be fairly certain that the battle system will likely be an evolution of the deck concept utilized in RE:coded, BBS, and 3D. Also, some merged form of the Style from BBS, Overclock from RE:coded, and Drive from KH2 will be in the game as well, plus some form of either player character customization or keyblade customization as in Days, 3D, and RE:coded.