Felidar Guardian was emergency banned last week. This is the stated reason why:
In Magic Online Standard Leagues since Monday, Saheeli combo has made up approximately 40% of 5-0 and 4-1 decklistsóup from prior to Amonkhet's release.
There's lots of disingenuous stuff going on here, but the real kicker is that players don't get the same access to data that R&D does; 4-1 decks aren't public and the 5-0 decks that get published are made public at the Magic Online team's editorial discretion.
What I'm getting at here is that based on the complete data that exists for post-Felidar Guardian Standard (last weekend's Standard Open, Standard Classic, and MTGO PTQ), Mardu Vehicles carries a roughly 25% usage rate, with an Open win. That'll be a number to pay attention to.
Even before Luis Scott-Vargas wrote The Official Basic Lands Power Rankings (a perfect post), I knew that those full art Zendikar lands sucked, but it was nice to hear the sentiment echoed. The Amonkhet full-art basics are sweet though. Maybe it's a result of the set having flavor that adds up to more than "stuff is floating in the air."
(I know I skipped a bunch of cards. I'm hopping around this week. Bear with me.)
Censor, the card everyone wished was Miscalculation, sees play lots of places. It's destined to be one of those blue cards that will go in any deck ó the only thing that will keep Censor out of blue decks is the deck-builders' preference.
To understand why all these cards sold like gangbusters this week, remember that tribal stuff, especially novel stuff, is always going to appeal to a broader playerbase. Amonkhet Zombies in particular are attractive to competitive and casual players alike because of Amonkhet's strong, flavorful pull and that the zombies themselves play in an interesting, grindy way.
This list doesn't have Liliana's Mastery in it, but Liliana's Mastery is a solid army-in-a-can card. It's not a stretch to imagine it featuring heavily in this archetype at some point.