So after many battles link regains the triforce and peace is returned to Hyrule. As for what happens to ganon, well he's sealed away in the sacred realm. Or so we thought. In botw we are briefed on the history of the first Calamity ganon battle, and we are told that ganon was sealed away using ancient sheikah technology, which just so happens to be under Hyrule castle. Coincidence? I think not. So through out botw we are told to take down ganon and when we get there to do it, we are met with this weird creature that resembles a spider and not ganon at all. I don't think the ganon we fight in botw is the ACTUAL ganon. And here's why, Calamity ganon is not an actual "figure". When we see him rear his head for the first time, sure he's a boar, but he's a swirling mass of coruption. Not an actual boar. Even when he roars, his bottom jaw seems like it's detached from his mouth. Well in the sequel I have a feeling we'll see actual ganon and here's why (cont)

So the greenish writing is floating above a body to which the remenants of calamity ganon are clawing at, trying to find a host. Link and Zelda are exploring this place, which I would think would be under Hyrule castle, so the place where ganon was sealed away. They find the body and see this almost majestic hand gripping it by it's chest. The camera zooms in on the body and we get a good look. The hair is long and red, the fingernails are long, it looks to have a skirt on but on the skirt is the symbol of the gerudo. Light flashes and it looks like the figure is in terrible agony, or was. So people are probably reading this right now and thinking, long red hair, long nails, skirt with gerudo, what's to say it's not Urbosa? Well I thought of that and here's why it isn't her. The facial build is that of a man, and if you imagine the figure with shorter hair, the resemblance to ganon is uncanny. Yes the figure has bracelets on, but on the other arm looks to be what is left of a sleeve, and Urbosa didn't wear a shirt, she wore a sort of crop top. As for the skirt? Well I think it was something ganon was changed into when he was seal away, but honestly that's still a mystery to me. (Cont)

The long hair and long nails makes sense since when you die your hair and nails continue to grow. Also we don't know much about regular ganon so it could be that he likes long hair and long nails. In the trailer after we see the body, link touches the magic writing, and breaks the seal that is Holding ganon. Through tiny clips we see the blue hand grab Zelda and we see a flashback from ganons memory, possibly showing what happened when ganon came upon this hand, so maybe the hand isn't so nice after all. It shows him bowled over in agony and he's wearing: surprise! A robe like skirt. Some like the Romans would wear, so that explains the skirt/robe. We also see that he has long hair, which he must have liked. So in this flashback we see that the calamity appears to be connected to the hand.... Which would mean there are greater forces at work and that ganon in botw isn't really ganon. Thus we encounter the ACTUAL ganon in botw2, but he's still going to be a puppet to whoever is controlling him. At the end, we see Hyrule Castle start to rise out of the ground. That could be more sheikah tech emerging, or it could be ganon and the hand's owner escaping to wreck Hyrule all over again, who knows.
Sorry this is so long! I didn't intend for it to be that way XD but that's my take on the trailer, here's to hoping it's released soon because it's not like they have to create all of Hyrule again, they just have to create a new story :)

just made a discovery after watching the video again xD i'm such a geek, in the video we see the opening to the "tomb" and at the end we see hyrule castle rising out of the ground, i've heard speculation that this could be a skyward sword twist, the floating islands in the sky, but i think it is actually the temple/tomb emerging from under hyrule castle. Which i feel makes a lot more sense than the skyward twist.
okay i'll stop now xD i like anaylising things and i went off the rails on this haha

*hops on the hype train* yes hello i'm ready to theorize

for one, i'll place my two cents on the different "forms" on Ganon
i think Calamity Ganon, all made up of malice, is the "true" form of Ganon, as it is pretty much the embodiment of evil in the Zelda universe - from the blood moon cutscene, it makes it look as if every monster is just Blight/Malice in a physical form, and it would also give reason to the dark smoke enemies poof into when you kill them in each game. the Imprisoned from Skyward Sword poofs into dozens of black drops every time it's defeated, for instance. also the name of "Malice," which kinda gives it away as evil in a physical, albeit goopy form.
the beast forms of Ganon: the boar one, making an appearance in BotW and TP, is the most primal. the other pig-monster versions (i.e. OoT, ALttP, LoZ, LoZ2, etc) are his attempts at being more "normal" and i guess like a fair opponent to the hero?
then you have Demise, who is the first incarnate of Ganon in a human form, but bears a lot of resemblance to the Imprisoned (black scales). he's also just the first appearance timeline-wise, and personally i think the timeline makes sense, so i'm going with it. iirc Vaati was the main villain while Demise was taking a nap and taking on a new name.
Ganondorf is just that evil taking a much more human shape, using the Gerudo as an outlet. i feel Ganondorf is a host for Ganon/Demise/the Malice. it would make a lot of sense for the rotting body in the trailer to be the original body of Ganondorf - after he was sealed away, he comes back in two different games as the same person. in Twilight Princess his execution by the sages sends him off to the Sacred/Twilight Realm, where he comes back having used Zant to take over the castle, but is then straight up murdered via previous stab wound. in Wind Waker, Ganondorf was left to drown with the rest of Hyrule until he eventually broke free. Link sealed him away with a nice stabby stab to the head. since BotW is a huge mix of every Zelda game (DLC and canon locations pointing to every game existing at some point, long, long ago) you could say that it's the same Ganondorf that was sealed in stone in Wind Waker. His head is held back in the trailer like it was when Link headshot him, and the glowy hand could be the essence of the old Sage sword that he was stabbed with in Twilight Princess trying to hold him back.
i've seen a lot of speculation that it's Urbosa's body, since if it was the same Ganondorf from TP/WW why would the clothes be different? well, i counter that with the fact that TP/WW Ganondorf is canonically the same from OoT but he's not wearing the same clothes there either so *shrugs*

alSO. the different Blights you fight in the Divine Beasts are also him attempting to try out different forms, and he obviously got a hand on some Sheikah weaponry, saying their weapons are all the same blue glowy ones.
in BotW i think it's less Ganon's power going wack more than just him trying to manifest again after 10,000 years, not being able to find a host and instead going beserk and not bothering to be more than goopy clumps of Malice

re:
ooh yes it being Demise would make sense! at least after so long he finally put on some clothes lmao.
there's a lot of speculation of Zelda being playable, and the fact her hair is cut short and she has a hood plays into that, since shorter hair would allow for more customization in armor. i listened to the trailer backwards a few times but i can't hear any of the words other people do. it being darker/as dark as Majora's Mask would be so cool, but seeing as the world is the same i don't think the whole game would be like that.
i can't remember everything i've seen either but one of my friends is hoping that there'll be a bit of co-op, seeing as how link and zelda were together

re:
aa i'd have to look again, my memory must be bad because i watched a skyward sword speedrun last night xP
i'd be fine with playing as Zelda most of the time. the game name would finally make sense and it'd be the first time Zelda was the main character of her own game series (we don't talk about the cd-i games). by the looks of the trailer switching back and forth between Link and Zelda doesn't seem too far off!
considering Link was only shown in the hylian pants/hood and champion's tunic and he turned out to have so much armor the game couldn't handle it, more outfits than the champion blue are definitely plausible.
i don't really mind when it comes out, especially considering i still have yet to fight Ganon lmao. i've been hunting koroks so that i get 100% first try xD

yES This is an amazing theory I love it!! I'm super hyped as well, it's gonna be amazinnggg

This is going to sound weird but now that Ganon has long hair, I want to see what he looks like in silly hairstyles, luke a man-bun or pigtails lololololol-