mtg khans of tarkir booster box as well as the chance to pull one of 500 serialized Headliner cards Wizards of The Coast Magic:

The timing is something we don't know, but the most logical thing would be that they arrive sooner rather than later and that, together with them, all dragon-type cards are updated.

Hit claim, and youve got it

Two additional one-off variations of Chaos Xyz Evolution were also seen in two episodes of ZEXAL : Episode 137: Vector performed a Direct Chaos Xyz Evolution (Japanese: Dairekuto Kaosu Ekushzu Chenji ) using "Rank-Up-Magic Admiration of the Thousands" to Xyz Summon "Number C5: Chaos Chimera Dragon" without having to use its base counterpart, "Number 5: Doom Chimera Dragon" as Xyz Material

You wont get to use these cards anymore, so I recommend tossing cards that are too expensive to play or not going to help you anytime soon