My take :
First off : I think the island was originally part of the surface. I mean, unless Pixel is ignoring the basics of our reality. A planet is where all the solid material usually is.
Now, could it have broken off naturally and begun to float because of some reason? Perhaps... but I think not.
How was the Floating Island created? (my ideas on it)
I don't think Jenka or Ballos created the island, but let me elaborate.
I assume the Core makes the island float. Why? Misery says so. Booster says so. That should cover both the tech side and magic side answers. And Jenka built the labyrinth to protect the Core.
But... there's more :
The Core isn't just a Core sitting in a damp cave. It's embedded in a Core Base, that could be as old as the island; as far as we know. We don't know exactly what the purpose of the Core Base was, but I cannot imagine that Jenka herself created the Base, nor can I imagine that the base was created there or teleported there; The Core seems all too well built for that area.
If you follow my logic, I think the Core Base is some kind of ancient tech, built close to the kingdom that Ballos lived in. Did it float at the time of Ballos' Kingdom? ... ... ... I don't think so. I mean, assuming the kingdom that was destroyed/Ballos' kingdom is the same one that is scattered on the island; it wouldn't be easy for people to have a large kingdom that is floating. Unless they can support that many people, or have an easy way to get on and off the island. It's just speculation though... I personally think it makes more sense that if the island is part of ballos' kingdom; then it wasn't floating at the time.
Now did Jenka make it float?
I don't think even she has the power to make it rip out of the ground; or create an organsim that will make it float. I mean don't underestimate Yoda, but seriously the island is BIG. Anyways...
Now, if you accept the Core Base being part of some kind of ancient tech, that created the Core/or can create and maintain Cores... Well... since apparently Jenka knows a lot about it, and has protected it. Perhaps she has control over the ancient Tech. (Perhaps the tech is magic/and tech)
My personal theory is that Jenka, and perhaps Misery has some control over the island. It's movement, how it floats, and who knows what else.
Now about Ballos' seal and Jenka... All Jenka could do was seal her brother; she couldn't kill him probably for the reason that Ballos is her beloved brother.
(About Ballos. Ballos apparently was a kind, amazingly powerful wizard. If Jenka has control over the island / Core Base/Core etc; perhaps Ballos has his own powers as well. Maybe he cannot control the island, but his magic power is nuts. Because he was a TRUE good guy, he wouldn't lift a finger to save himself when he was being tortured. Only when his mind was gone, and all that was left was his POWER; the kind Ballos that Jenka knew probably died.)
Jenka, seeing what has happened created a seal. Placing her brother in it, as it was all she was willing or capable of doing. She then controlled the ancient power of the island, and it floated away, so that the world that did this to her brother would never again cause the same pain.
As for Mimigas and creatures //// my personal idea is that any survivors were probably cursed by Jenka or someone/ just like Sue and Itoh were by Misery, to become Mimigas. (they are pretty weak unless they are frenzied)
Was Misery born already at the time of this disaster? I have no clue... if she was, then she probably had the biggest shock of her life. From peace to misery overnight. I wonder if Misery was her real name... or if it's one of those words that are jumbled up to be something else/slightly changed etc. Who would call her daughter Misery anyways...
Misery should have friends... instead she has Balrog! (no offense my friend
)
Anyways, instead of going on and on; Let me sum it up.
Accepting all that I said here's the summary :
The island was part of Ballos' old kingdom. It probably didn't float at the time of its disaster. But, Jenka knew how to make it float. The ancient tech deep, deep within the earth was probably connected to both Ballos, and Jenka's bloodline. Using the Core's power she made it leave the earth, and sealed Ballos within.
(About the Seal. I think it's something like a timeless seal... Meaning it doesn't really degrade over time as long as it is contained. Perhaps Jenka was able to make the Core contain or even feed off of Ballos' negative magic. It would keep Ballos from being able to become as dangerous as he could be.
The Seal Room is like a giant hell trap. All the people that he killed probably make up the floor, walls etc... All those trapped souls were probably put there by Jenka to create an ultimate trap that forced Ballos to be trapped there.
)
Oops gotta go... later
