Hi LK and welcome to Kingdom Hearts: World Destiny. I am Ellie, and I shall be assisting you with your profile.
EVERYBODY DANCE NOW *dances*
Okay anywho!
Age: She'll be 15. This rpg is a year after kh2.
Power:
Subspace - This is a very random power you stuck in here; you mention it as a family skill very late in the history, which only makes it more random. There's nothing to atest to her obtaining this skill, working with it, or bettering at it.
Also with KH the only known other dimensions are 'dreamscape/heartscapes (your awakening scenes', realm of darkness, and realm of between. If you're going to try to save this, it would make since if its one of those, but it can't be the last 2. Sure people before have made their own crafty dimensions, but that's only within the bounds of the characters' imagination not reality. (for example Zexion's book.)
Why?
A.) We don't allow everyone and Kairi's grandma to manipulate the corridors of darkness, because it's not a common ability to the general public unless youre truly neck deep in darkness.
B.) That other is yeah
hardly known.
If you're going to go through a 'heart scape of 'dive into the heart' you need some good explanations in how she acquired that skill.
Technique
Scan: I doubt Scan would be very useful here. It's one of those details that functions well in a game, but not in a rpg setting. I doubt a charrie would need a scan ability to see if someone's fawked up or not.
Libra on the other hand (pretty much its FF counterpart) would be more resourceful. Check it out and use it as a replacement if you wish.
Weapon:
I'm lost. You describe it as a sword, then it's swords, then it's a scythe. What is it exactly? The name Syphon Scythe automatically makes me think it's a scythe, buuut it's not.
How much magick does it takes? Since this will affect her opponents, you should detail in how it affects them, their mana, and spell casting abilities. Those it takes so much that it halves their overall mana, or momentarily lower their abilities. Also how long is this giant sythe is activate, and you should describe giant.
History:
Alright we have some holes to adjust, but don't be overwhelmed because there's a method to my madness.
+ You should have everything in chronicle order. You mention BBS occurs when she 3 after you talked about when she was 8.
+ How does her brother even know of the keyblade masters, keyblades, or other worlds? Generally those things goes hand-in-hand, and that knowledge isn't widely known to all the worlds. (Also Sora isn't a keyblade master yet, just a wielder.) Also how did he knew the worlds were endangered? You haven't mentioned any heartless attack on their native world. Also how did he leave his world to go search for the keyblade?
+ Also you should re-work how she leaves the world, since we're offing the subspace poofage.
5 daaaaays!