Just in: It has been rumored for the past few days that the four adult Dragon Rulers would be in LTGY as regular Rares and that their younger versions would be common. Today, a picture has appeared online that appears to prove this:
Fun note: The box of LTGY in the background appears to have the name of the set written in Spanish, which is the same language as the leaked Sneak Preview card list that first made headlines last week.
Update #1 (5:03pm EST): Moments after posting this, I've found more pictures which depict the rarities of other cards in LTGY as well. Check them out below:
Picture #1: http://imgur.com/pKfIPwq
-Spellbook of Miracles appears to be Common
-Blaster, Dragon Ruler of Infernos is Rare
-Mermail Abyssbalaen is Ultra (though we knew that since the release of the official Product Page)
-Spellbook of Judgment is Secret
Picture #2: http://imgur.com/zjqENCJ
-Cardinal is Secret
-Seven Star Sword appears to be Super
-Gauntlet Launcher is Ultra
-Number C105 is Ultra
-Evilswarm Kerykeion is Super
Thanks for reading! I'll continue to update this post or create new ones if more info comes out.