User blog comment:BlurayOriginals/Blu's TalkBlog/@comment-1478167-20120111180155/@comment-995908-20120111213738

Dialga and Palkia weren't Pokeball-summons; they had their own stages. So I think Zekrom and Reshiram should have their own stage as well.

Pokeball summons that I'd want to see are;
 * Landorus (uses ???)
 * Thundurus (uses ???)
 * Tornadus (uses ???)
 * Cobalion (uses ???)
 * Terrakion (uses ???)
 * Virizion (uses ???)
 * Kyurem (uses Glaciate)
 * Meloetta (uses Ancient Song)
 * Druddigon (uses ???)