Codex was a huge success on Kickstarter. It's shipping to backers a whopping 3 months early! We're now taking pre-orders for it here. Pre-orders will ship after orders to backers ship, so probably by September 2016 or October at the latest.
You'd don't have to get the Deluxe set, but it sure is fancy! You can always start with the $25 starter set or the $50 core set though.
Codex is an RTS-video game in card form. It's also a reinvention of the CCG genre. It's coming at things from a much different direction than other CCGs. You can read more about the game's design (23 articles about it!) and listen to a podcast about it, here.