When it comes to tournament Magic, sometimes the Top 8 tells you the whole story, and sometimes it doesn't. The Pro Tour this past weekend was one of the cases where the whole story wasn't obvious; even though Red-White Aggro was over-represented in the Top 8, it didn't actually dominate the tournament, and players (and wins) were split between the major archetypes of Izzet Drakes, Golgari Midrange, Red-White, Mono-Red, and Jeskai Control, with a couple of guest appearances by Boros Angels, Mono-Blue, Esper, and different flavors of Selesnya.
Of the major archetypes that didn't make the Top 8, Golgari Midrange is the most customizable one, and the one I feel has the best chance of success going forward, so it's the one I will focus on today.
Here's what I believe is the best performing Golgari Midrange list from the tournament, from Top 16 finisher Michael Kundegraber:
Golgari Midrange is a deck that has existed since the dawn of time, and its game plan has always been relatively consistent: to pair the overpowered green creatures with the overpowered black disruption. In Modern, this is done mostly in the form of discard spells and cheap removal; in Standard, we don't have the discard spells, but we get to play more removal and then have a better late game because of planeswalkers.
Every deck that isn't trying to close out the game quickly needs some form of card advantage, and in this iteration of black-green, it comes mainly from the explore creatures and the planeswalkers. There isn't an Expansion // Explosion type card that will provide you all the advantage you need in a single turn—instead, you get to grind your opponent with incremental two-for-ones. This is also one of the few decks in the format that gets to play a good utility land (Memorial to Folly), though there is only one copy here.
As far as the specific list is concerned, the thing that jumps out to me is the lack of Wildgrowth Walker (and its replacement by Druid of the Cowl). While I understand what Druid of the Cowl does for you, I think Wildgrowth Walker is just too important in this metagame, and I'm surprised Michael is not playing any. In fact, I'd go as far as saying that I just wouldn't play the deck without four Wildgrowth Walkers in it (KMC-Genesis and Ultimate Guard Pro Team, for example, played two). It's literally your best card versus White Weenie, Mono-Red, Drakes, and Mono-Blue, since the combination of life gain plus a big body ensures you're very hard to race.
Another card I like that Michael isn't playing is Doom Whisperer. It's not that good in the mirror, since it can just be killed (as opposed to Carnage Tyrant, which Michael has four copies of), but it's great versus White Weenie, Mono-Red, and some draws from Drakes (it's always excellent unless they draw Beacon Bolt). It's cheaper than Carnage Tyrant and a better blocker, since it flies, and it also helps you find whichever removal spell you need—Doom Whisperer into Find // Finality is a powerful curve.
When you build this kind of deck, you always have to decide what you want to beat. If you want to beat control and the mirror, then Carnage Tyrant is the superior choice hands down. Personally, right now, I want to beat Drake, Mono-Red, and Red-White Aggro more than I want to beat the other two, so my choice would be Doom Whisperer. Then, I would try to shore up my weaknesses to control and the mirror in my sideboard.
My favorite Black-Green list in the tournament is actually from Matthew Nass, who also went 8-2 in Constructed but ended up finishing worse in the tournament because of his Limited record:
I like Matt Nass's list because it's very well tuned to beat what I perceive to be the most popular decks going forward. Having three copies of Cast Down, for example, is excellent against Drakes, Mono-Red, and Red-White Aggro—almost everyone else plays one or at most two copies, relying on Assassin's Trophy instead, which is worse versus all of those. On top of that, he also has Doom Whisperers and the full four copies of Wildgrowth Walker. The downside, of course, is a worse mirror and control matchup, but I think this dedicated approach is better than trying to be decent against everything, which often results in beating nothing.
In the wake of the Pro Tour results, I think this list is a very good choice. It's the best version of Black-Green versus Red-White Aggro, and it's also good against Mono-Red, which might be everyone's go-to deck to beat Red-White Aggro. If I were playing a Standard tournament next weekend, this exact list would be a strong contender.