Black-Green Delirium burst into Standard by claiming both finals berths at Grand Prix Providence and cementing itself as a natural foil to the White-Blue Flash deck that was the best deck from the Pro Tour the week prior. Black-Green Delirium seem to be tailor-made to defeat White-Blue Flash. For example, Liliana, the Last Hope matches up well against its many two-powered creatures - exemplified by Ishkanah, Grafwidow presenting a serious roadblock for Flash's offense. Flash decks have fought back, specifically with Revolutionary Rebuff or more extreme technology like Always Watching, but it's an uphill battle.

Black-Green Delirium can also claim a strong matchup against Red-White Vehicle decks, including Mardu Vehicles, where Liliana, the Last Hope destroys even more creatures than against Flash, and Ishkanah, Grafwidow is even harder to overcome. Delirium is a powerful midrange deck that includes many of the best mythic rares in the format, so it's strong against the various lower-tier and rogue decks in the format based on card quality alone.

These facts add up to mean that Black-Green Delirium currently holds the crown for the "best deck" in Standard. It has been a slow process, but during the last month the metagame has seen a continual shift away from Flash and Vehicles decks and towards Delirium. The peak of Black-Green Delirium's greatness came with Brad Nelson's win of Grand Prix Knoxville.

A player with the Standard pedigree of Brad Nelson winning an Open is a big sign that a deck is on top of a metagame, but more telling is the trail of Delirium decks behind him, with two more in the top four and another in the top eight - and World Champion Brian Braun-Duin looking in at ninth place. There are surely many players who made the switch to Delirium after Brad's win, and indeed in the week following the deck was more popular than ever.

But the best days of the deck may now be behind it.

On the digital card tables of Magic Online, where the games never stop (except during downtime), and you can switch decks at the click of a button, the metagame moves at breakneck speed. Tens of thousands of players playing matches day in and day out means the metagame evolves faster than in the paper world. As a comparison, think about the rapid pace of evolution of quickly-reproducing bacteria compared to animals. If a deck becomes too popular or dominant, the metagame begins to balance itself out as that deck's foil appears and begins to prey upon it and erode its market share.

Rather than get bogged down in muck with Black-Green Delirium, players have begun to adapt and discover how to rise above and win on their own terms. Fighting fair against Delirium is a losing battle, because it's a fight they are specifically designed to win as a true midrange deck. Innovative players have found that the solution is to go over the top of Delirium with a more powerful strategy that their cards aren't prepared to stop. They've turned to the strategy that kept Delirium from being competitive all the way back at the Pro Tour, Aetherworks Marvel, except it's remodeled and updated for the realities of the current metagame.

Moving Aetherworks Marvel away from an all-in combo deck and towards a more midrange plan with Ishkanah, Grafwidow allows it to stay competitive with Flash decks. The backup plan of simply casting Emrakul, the Promised End is an endgame that Delirium decks can't reliably beat. Red-Green Marvel has proven itself to be the best solution to Black-Green Delirium that remains competitive against the rest of the field, so it has been quickly gaining popularity on Magic Online as players seek to replicate its successes. Red-Green Marvel has now surpassed Mardu as the third-most popular deck, which moves the metagame closer to a true rock-paper-scissors situation of Delirium, Marvel, and Flash fighting for supremacy.

With the cat out of the bag about the power of Aetherworks Marvel, there has been further exploration of it applied to a midrange strategy. The most successful alternative to Red-Green thus far is Black-Green Marvel, which mashes the Aetherworks Marvel plan into something resembling a Delirium shell, which in some ways makes this deck seem like a successor to Black-Green Delirium as much as it is an alternative to Red-Green Marvel.

Black-Green Marvel quietly finished in 12th place in Knoxville in the hands of Brad Carpenter, and it has gained a small following on MTGO that continues to refine the strategy.

Black-Green does have some unique advantages compared to Red-Green. Noxious Gearhulk is a fantastic addition to the midrange plan and better than anything available in red. It makes Aetherworks Marvel even more reliable as an additional game-changer, but it also makes it less necessary because the deck is more capable of winning a fair game. Noxious Gearhulk can kill Emrakul, the Promised End, and black provides discard to the sideboard, so the black-green deck would seem to have an edge on the red-green version, and that could be important given the momentum red-green is gaining.

Black also provides Liliana, the Last Hope, which is very effective against aggressive decks like Flash and Vehicles, and makes this deck very potent at playing a fair game that can resemble Black-Green Delirium, A major downside to black is that Grasp of Darkness is inferior to Harnessed Lighting. Harnessed Lightning is easier to cast and can potentially destroy larger creatures, but the key factor is that it can help activate Aetherworks Marvel.

This sideboard features multiple things I like, starting with the fourth Ishkanah, Grafwidow as the first sideboard card. It's simply the most effective and powerful card possible against White-Blue Flash, so any sideboard spots dedicated to Flash should begin here. Demon of Dark Schemes is a powerful black card that can come in a few places - it's great against aggressive decks, but it also seems quite strong against Black-Green Delirium, where it clears out any spider tokens, blocks Mindwrack Demon, and can use its activated ability to take over the game.

Grim Flayer allows the deck to shift even further towards a midrange deck and makes it much easier to win without Aetherworks Marvel or Emrakul, the Promised End. This point is valuable considering that opponents routinely bring in disruption like counterspells and discard that can make these expensive cards ineffective, and alternative win conditions will only become more important as opponents prepare specifically for Marvel decks.

I'd like to further explore the idea of a transformational plan by adding some Tireless Tracker to further the deck's ability to play a midrange game. Black-Green Marvel looks like a great alternative to Red-Green Marvel, and it might be the best option for Black-Green Delirium players looking to adapt to the new metagame.

Black-Green Delirium will have to adapt to the influx of Red-Green Marvel if it hopes to remain competitive, and the matchup is poor enough that it will require some dedicated solutions. One Black-Green Delirium player has seen repeated success in the past week in a metagame infested with Marvel, but their sideboard may hold the key to their success.

The technology of Lost Legacy is effective in the mirror match to strip the opponent of their few relevant threats, but it's in the sideboard primarily to eliminate the threat of Emrakul, the Promised End from Aetherworks Marvel decks. It makes their deck much more manageable and forces them into a fair fight that Delirium is favored to win. It's much more reliable than Pick the Brain in this role because the opponent won't always have Emrakul, the Promised End in hand, and unlike Transgress the Mind it's never going to completely miss the mark, especially as a topdeck later in the game. The combination of Lost Legacy, Pick the Brain and Transgress the Mind - and potentially the addition of Distended Mindbender as a Traverse the Ulvenwald target - gives Delirium a chance at disrupting Marvel decks enough to beat them with aggression.

On the topic of aggression, the most viable route for Black-Green Delirium to navigate the metagame ahead may be to shift into a focused aggressive deck that's much better equipped to race Red-Green Marvel decks. This makes its discard disruption even more effective because the opponent will have less time to draw what they need. Aggressive black-green decks aren't unprecedented, and in fact the most successful black-green deck at the Pro Tour, where Aetherworks Marvel was everywhere, was an aggressive version with Smuggler's Copter. That strategy has been pulled off the shelf by a savvy few, and it earned a second-place finish in the Magic Online Pro Tour Qualifier last weekend.

This deck has been streamlined since we last saw it, now including a set of Scrapheap Scrounger as an aggressively-oriented threat that combines well with Smuggler's Copter as the perfect card to discard and reliable crew. Its inability to block was a liability in the Vehicles metagame of the Pro Tour, but now it shines in midrange metagame. This deck includes a full set of Mindwrack Demon, which has superior delirium synergy compared to Kalitas, Traitor of Ghet. It also survives Grasp of Darkness against Delirium, rules the skies against Flash and hits harder against Aetherworks Marvel, so it's better all-around in a metagame where aggressive decks are uncommon.
.Racing is the name of the game of this aggressive deck, so Verdurous Gearhulk is the five-drop of choice that can add surprise power to the board and help navigate any board stalls. The defensive Ishkanah, Grafiwdow is retained in the sideboard to help shift gears against the matchups where it shines, specifically against Smuggler's Copter decks.

A more recent version of this deck remains truer to the original, with some Servant of the Conduit and Catacomb Sifter in addition to Scrapheap Scrounger, while forgoing Gnarlwood Dryad entirely.

The mana acceleration of Servant of the Conduit and Catacomb Sifter is a strong inclusion against an Aetherworks Marvel metagame where time is of the essence. They will also help against Black-Green Delirium, where speed is important to race Emrakul, the Promised End, and the grinding ability of Catacomb Sifter will be useful against their removal spells.. Gnarlwood Dryad is poor against Delirium since Liliana, the Last Hope destroys it, and aggressive decks where it's a great blocker aren't a large presence, so this deck is specifically tailored for beating a metagame of Aetherworks Marvel decks. The sideboard goes even further than Transgress the Mind with a pair of Distended Mindbender as extra discard against Aetherworks Marvel decks and another tool against Delirium decks - made possible by Catacomb Sifter and Servant of the Conduit.

An alternative and admittedly completely untested idea for Black-Green Delirium I found when searching the internet for any other alternative black-green strategies I could find, straight from the TCGplayer State Championships.

This approach to Delirium attempts to use Marionette Master as a source of battlefield presence and a finisher when combined with the clue tokens of Tireless Tracker. To help sacrifice clues even faster, Syndicate Trafficker steps in as a great threat. This decklist could surely use some tuning, but it's a reminder that black-green does have some other great cards available, and they only stand to get better with the release of Aether Revolt.

What's your perspective on how Delirium can weather the storm of Aetherworks Marvel decks? Share your ideas in the comments, and I'll answer any questions!