This is the updated version of my previous attempt at a treasure-focused control deck, only using the new cards from War of the Spark. Much was changed from that version before even going for this premature brew. I also took some inspiration on TuesdayTastic's brew, mainly the Karns and Jhoiras. 

Now that WAR is fully spoiled, I can work on this deck again. 

The deck itself revolves around Saheeli, Sublime Artificer's ability to create servos, in an attempt to generate massive amounts of mana thanks to Storm the Vault // Vault of Catlacan, to finish the match with a glorious Expansion // Explosion (or Banefire). Should that fail, we have backups on the tokens themselves, being 1/1 creatures, on Karn's -2, and an average Explosion or Banefire. 

The wincon shifted a bit towards Bolas's Citadel in this recent iteration, as once it hits the board, we gain massive card advantage and power. This frees up a couple slots, but strains the mana base, so we'll see how effective this change is. Mizzium Tank offer some aggression and, seeing how literally all of our spells are non-creatures, it'll almost always be enabled. And even if we have zero spells to cast, a single Saheeli servo is enough to crew it. It ends up being a secondary wincon thanks to its strength. 

Due to the shift in wincon, I dropped the Powerstone Shards. They have excellent potential for raw mana generation, especially with Saheeli's copying ability, but they're too slow and offer zero benefit beyond colorless mana. They became less useful after Bola's Citadel was announced. 

The new Ral, Storm Conduit's role is copying stuff. A copied fire cannonade lets you deal with the average selesnya board; a copied Explosion or Banefire would let you seal the match sooner. It also offers some (admittedly minor) card selection, and has the potential to deal infinite damage with two Expansion // Explosions.

I've dropped Jhoira, Weatherlight Captain because she was slow as well, and the card advantage offered was made less valuable after the citadel. 

As for the Sideboard: Electrodominance and Mass Manipulation are both X cost cards (duh) so they benefit massively from our potential mana generation. Electrodominance can let us cast stuff at instant speed while dealing damage, making it pretty useful. Bedevil is present to handle problematic artifacts, mostly, but can also be used on the other types. Recommended to add Electrodominance together with it to help you cast it, but you shouldn't have too much of a problem casting it with the 4 shocks and treasure generation. Mass Manipulation lets us steal planeswalkers, which I'm guessing will be extremely relevant in the upcoming set. 

Maybeboard: Augur of Bolas could find a spot on the maindeck, as we have 13 cards it could fetch us, with 6 of them being finishers and 4, refuelers.
Role Reversal seems fun, as well, stealing an opponent's key artifact/creature and leaving them with a 1/1, but it strikes as a bit of a meme, really.
Commence the Endgame looks amazing, but is so, so, SO expensive! 6 mana for a draw two spell is a lot, even if it's uncounterable. Naturally, it also comes with a body, so this makes the card excellent when facing control decks. Still, I'm reluctant to add it to the sideboard, let alone mainboard, due to its manacost.
Finale of Promise lets you recycle some spells from your grave. For us, that would be almost exclusively removal in lava coil and bedevil, making it rather unimpressive. Still, it's an interesting card to keep in mind, especially if we add Commence the Endgame somewhere in our 75 cards. 

I'm open to suggestions!