In terms of where to buy, TCGplayer is the most reliable option, but also the most expensive, so proceed only with the knowledge that you're paying a premium. Amazon is sticking to matching market ...

Z-A downloadable content “Mega Dimension” has added Mega-Evolved Pokemon Mega Garchomp Z as of today, publisher The Pokemon Company and developer Game Freak announced.

Amazon is listing the ETB for $109.88, $10 off its Pokémon Day pricing of $119.99. If you consider delivery costs, it's pretty neck and neck with TCGplayer right now. All things considered, I'd say ...