Combo is back in Standard, thanks to one very sweet Kaladesh card.
Aetherflux Reservoir is like a reverse-storm finisher. Instead of needing to resolve a bunch of spells before your Tendrils of Agony or Brain Freeze, the Reservoir can come down first and set up going off later. Reservoir also has more application in most scenarios than a card like Tendrils would when you can’t actually go off. Just by casting 2-3 spells per turn, you’re gaining 3-6 life. This can be critical to survival against the aggro Copter decks in the format as you prepare to go off.
“Going off” in Kaladesh Standard will revolve around the new Paradoxical Outcome or the old Crush of Tentacles. Both will allow you to bounce all of your nonland permanents in order to replay a bunch of spells with your Reservoir.
Paradoxical Outcome is far better at accomplishing this goal in this style of deck. First off, you can choose which permanents you’re bouncing. This means that you can choose to leave your Aetherflux Reservoir in play and just bounce the cheap stuff to go off in a single turn. With enough mana, you can cast the 9 spells you need in a turn to gain 45 life and one-shot them. This can also be accomplished with enough spells that happen to cost 0 mana. Paradoxical Outcome rewards you heavily and makes it far easier to pull off by also allowing you to draw a card for every spell you bounce, ensuring a higher likelihood of hitting more cheap spells, or perhaps just another Outcome to finish the job next turn.
Crush of Tentacles goes about this in another way. By bouncing both everything you have and everything your opponent has, you’re buying time. You also force them to deal with an 8/8 creature. Crush can come down extra early in a deck that happens to play really cheap spells that cost as little as 0 mana. While bouncing your Aetherflux Reservoir isn’t ideal, making your opponent reset completely while gaining life should buy you the time needed to win.
Outcome, Reservoir, and Crush all work best with cards that cost 0 mana, but other cheap spells will do. This deck is not looking to use Bone Saw or Cathar’s Shield for their ability to equip a creature, but merely as spells that cost 0. A turn-4 Aetherflux Reservoir means you can cast 3 of these zero-mana artifacts, bounce them all with Outcome, draw 3, replay all 3, and then you only need a single other spell that costs 1 mana or less to deal 50 on turn 5.
To set this up, you’re going to need ways to see and draw more cards. You’re looking to assemble tons of cheap spells, and a couple of the important cards to actually finish the game.
Glint-Nest Crane is a sweet one as a reasonable blocker that allows you to Impulse for the requisite artifacts, or the Aetherflux Reservoir, needed to win the game. With all of the zero-mana spells being artifacts, and many of the cheap card draw spells also being artifacts, Crane is a great enabler. Contraband Kingpin works similarly. It can block early creatures and helps you with card selection by getting a scry out of every artifact.
Attune with Aether and Traverse the Ulvenwald will help fix your mana. You’re looking to play a low land count to make sure you’re hitting spells you can cast off of your Paradoxical Outcome. These are cheap spells that function as lands, but will still gain you life off of Aetherflux Reservoir.
Metalspinner’s Puzzleknot and Prophetic Prism are the final pieces of the Kaladesh puzzle. These are cheap artifacts that help you dig. You’re happy to find them off Crane, to scry and draw off of the Kingpin triggers, or to bounce them for value with Crushes and Outcomes. These are your heavy lifters to get through your library and find the critical combo pieces.
Reservoir Storm is an awesome deck that still needs work to find the perfect build. It’s surprisingly capable of going off quickly, threatening to deal 50 on turn 5, and can offer some decent resistance thanks to the creatures and incidental life gain triggers. If Jeskai Ascendancy Combo was your deck, if you’re a Storm player, or you just like to do sweet things, this is the deck for you!