http://www.famitsu.com/news/201407/08056716.html
Details from GAF:
Quote
New characters: Fi (playable), Ghirahim (enemy), The Imprisonned (enemy).
Also: new item (the big ball from Twilight Princess), and Skyward Sword costumes for Link and Zelda. Looks like Zelda got a new weapon too, but hard to tell with that tiny preview.