
Every set needs an exciting dragon. At least, that's the logic behind
Balefire Dragon and
Moonveil Dragon. However true it is for a gothic horror set, there can be no question how important it is for a core set. The number one thing players will be disappointed not to see in the set that introduces them to Magic is an impressive dragon. There are 98 cards with subtype "dragon" and many more cards that interact with or even just reference them. Right now Magic 2013 is looking for its poster dragon. It could be a reprint, but it needs to be worthy of mythic rarity, appropriate to the setting-neutral environment, and feel refreshing.
Bogardan Hellkite was a great inclusion in M10, but would be a bit repetitive to bring back again so soon.