With the recent bannings, I'm even more focused on this card:
Without Emrakul, the Promised End to keep midrange decks in check, I'm looking to be the king of midrange. Tezzeret the Schemer could be excellent in that role. It provides a quick clock, card advantage, removes threats, and plays well with many of the new cards in Aether Revolt.
Another thing I'm excited for is the endless possibility in deckbuilding with Tezzeret the Schemer. The mana fixing right now might be a little too good.
If you start a Tezzeret deck with some of those cards, you can basically do whatever you want. Even Tezzeret himself is going to fix your mana. You can build Tezzeret decks built on raw power (like a more aggressive Tezzeret deck), but regardless, you're going to need synergy. Each color has cards I'd like to pair with Tezzeret, and thankfully the mana fixing makes that easy.
I should note that none of these decks are built with the Saheeli Rai / Felidar Guardian combo in mind. I'm aware of its existence and it will probably be played to some degree, but in what numbers and in what shell, I have no idea. Because of that, I'm showcasing some "normal" decks here, not ones that are tuned to beat a deck that may or may not exist. If you think the combo is going to be popular, you probably need things like Shock, Authority of the Consuls, Implement of Combustion, and Thalia, Heretic Cathar somewhere in your 75.
Similarly, while Emrakul, the Promised End is gone, Ulamog, the Ceaseless Hunger still exists. I'm not packing a lot of Disallows in my decks at the moment because I'm not sure how good the Aetherworks Marvel decks are going to be. I still have Metallic Rebuke in large quantities, and it's incredibly unlikely for them to hard-cast Ulamog the way they used to with Emrakul. All you have to do is counter Aetherworks Marvel and have a way to deal with their planeswalkers and Ishkanah, Grafwidows, and you should be fine.
As far as aggro is concerned, I think those matchups got a lot easier. They didn't gain much from Aether Revolt, and losing Smuggler's Copter means your removal is better against them. In the majority of these decks, I'm building as if these decks exist, but not attacking either pillar any harder than the others.
There are several energy cards that are artifacts or make artifacts, so combining those with Tezzeret seems natural.
What are our energy payoffs? What are the best cards that make energy? My first draft has Whirler Virtuoso and Woodweaver's Puzzleknot in those slots, but I wouldn't be surprised if I was wrong.
This deck is basically me trying all the things while being somewhat unfocused. In a tournament setting, that's probably the wrong approach, but when I'm testing new cards, I mostly want to get a feel for the interactions and see what's possible.
With Maverick Thopterist, you want to be able to Improvise it early. Since you can already Improvise and you gain two additional things to Improvise with, it's possible you could try for something large like Whir of Invention.
With cards like this, the only things that matter are how easily you can cast it and how powerful the cards are that you're searching for. We don't have a wide array of value artifacts to search for, so this isn't going to feel like Chord of Calling or the decks that card is typically in. Instead, I think it's going to end up being a card you use to search for combos or end-game finishers like Gonti's Aether Heart.
The manabase is kinda great. There are so many dual lands that mostly don't have downsides, so you can do wild things like splashing Tireless Tracker for your sideboard. This next deck attempts to tighten up the energy package and eliminate weirdo splashes.
Maverick Thopterist (and improvise in general) kind of has the "Affinity" feel, so obviously I want to build around it. My next goal is try going all-in with things like Herald of Anguish and Sly Requisitioner.
This deck is trying to go wide with Thopters and eventually finish off the game with Gonti's Aether Heart and a Tezzeret ultimate. Decoction Module is something that could potentially be played in higher numbers and gives you a discount on Whirler Virtuoso.
The UUU portion of Whir of Invention can be tough, but we do have Terrarion and Prophetic Prism to help. If you're going for a big artifact with Whir and need to sacrifice your Terrarion instead of using it for Improvise, that's not ideal. Maybe the manabase needs to change some?
Elder Deep-Fiend is pretty nice with Maverick Thopterist, but that's likely something for a different deck. You could go even deeper with more Wandering Fumaroles and Whir of Invention for Crackdown Construct as an additional combo finish. Maybe you want Key to the City or Baral's Expertise at that point? I wouldn't make the combo into the focal point of the deck, but it might be something you could use a Whir of Invention on in the mid-game to steal some wins.
We're blue and red, plus we have artifacts and enters-the-battlefield abilities. Should we just play Saheeli Rai? If we do, should we just splash Felidar Guardian? With all the Thopters, Ongoing Investigation isn't crazy. We could also go another route with Pia Nalaar and/or Reckless Bushwhacker. Glint-Sleeve Siphoner is another energy payoff that I haven't incorporated into any of these decks, but I probably should.
Despite being a more controlling deck, this deck can operate on a low-ish land count thanks to Renegade Map, Prophetic Prism, Metalspinner's Puzzleknot, and the fact that it doesn't have strict color requirements. In most cases, I think you'd prefer to keep Renegade Map around for Improvise or Revolt, but you should be fine either way.
Metallic Rebuke, Fatal Push, and Liliana, the Last Hope will keep you alive in the early-game. Your mid to late game is a combination of Walking Ballista, Noxious Gearhulk, and planeswalkers. I'm also trying a Magnifying Glass to see how truly bad it is.
Hedron Archive might seem odd, but I felt like I wanted more mana producers for Walking Ballista and Pacification Array. If that ends up not being necessary, I could see more Metalspinner's Puzzleknots and/or more threats.
Tireless Tracker is a powerful sideboard option, but obviously it would require retooling the manabase to include Botanical Sanctum, Blooming Marsh, and Spire of Industry. At that point, you'd probably have to cut Sunken Hollow. You could even go full delirium mode with Ishkanah, Grafwidow if you wanted to. I'm not a huge Evolving Wilds fan, but it works well with Tireless Tracker and Fatal Push, so maybe it's worth it, especially if you're including more green cards.
I like the sideboard as is, though. With Gifted Aetherborn; Kalitas, Traitor of Ghet; Battle at the Bridge; Noxious Gearhulk; and even Inventors' Fair; this deck has a lot of lifegain for B/U. Between that, removal for planeswalkers, and a pile of counterspells, I like what this deck is doing.
Maybe this isn't quite as good as B/G Delirium was, what with its Emrakul, the Promised End game, but it doesn't have to be. Instead, we can focus on beating people up with Tireless Tracker and its army of 5/5 Clues.
There's a wide spread of card types for delirium, so I imagine you'll reach it naturally in most games. It's actually kind of sick how easy it is to achieve these days. The manabase might look ambitious, and maybe it is; however, Terrarion will probably carry you pretty far on things like Liliana, the Last Hope. For everything else, there's Traverse the Ulvenwald, Prophetic Prism, and Evolving Wilds.
Scrapheap Scrounger and Tezzeret the Schemer were kind of made for each other. You can use Tezzeret as a way to accumulate value for bigger spells or improvise, but it's also possible to use it as a beatdown machine. Scrapheap Scrounger adds to that plan, is an artifact, and crews most Vehicles well.
When building these Tezzeret decks, one of the common themes is finding a one-drop artifact or two that plays well with the rest of the strategy. Those feed into Improvise, allowing for things like Metallic Rebuke on turn 2. Without an artifact on the first turn, your deck becomes much worse.
This deck not only has Thraben Inspector but Renegade Map and Consulate Dreadnought as well. Consulate Dreadnought is cute, especially with the various Auras that turn on Vehicles, but Peacewalker Colossus is a card I haven't seen many people talk about. It seems kind of slow, and maybe it is, but if you get it going, your opponent is going to take a ton of damage.
This is definitely one of those decks where losing Smuggler's Copter hurts a lot, as it really wants some earlier plays. While Heart of Kiran doesn't exactly replace Smuggler's Copter, it is oddly better with Metallic Rebuke thanks to vigilance. Hedron Crawler could fit, especially with Reality Smasher maindeck.
Three Aether Hub might seem like a strange number, but if you have no other ways to produce energy, you certainly don't want to draw a bunch of Hubs. Granted, this deck's colored mana costs aren't intensive, so maybe it's not an issue, but it's a small deckbuilding decision that I think is correct.
Tezzeret the Schemer might not fit here either, but I wanted to play something that generated value for Felidar Guardian to blink, and Maverick Thopterist "fit" in theory and so did Prophetic Prism. Obviously we need some artifacts to make that card playable, and then it was a slippery slope to Tezzeret.
Glint-Nest Crane would be a decent addition if the deck had more artifacts, especially if we were talking about the combo pieces.
To start the combo, you need to put a counter on something, so we need things like Implement of Ferocity, Syndicate Trafficker, or Ruins of Oran-Rief. Contraband Kingpin and Glint-Nest Crane help you find the combo. As always, going full combo with poor enablers and poor searchers is likely worse than sliding Metallic Mimic and Animation Module into a reasonable beatdown deck, but oh well.
I'm willing to bet some of these decks are very bad, and that's okay. This is my starting point. As of right now, I'm satisfied with the Delirium, Control, and focused Energy builds, but there's still plenty of work to be done.