This is a refined and battle-tested Heliod, the Radiant Dawn
cEDH deck, currently with an 11-8 record at my pod's table (yet, I argue it's better than that), and it's always played against their top decks as well (I won't bring it out unless everyone is bringing out their best decks too). There are many reasons this deck plays as well as it does, but chief among them is that it's built around massive card draw, massive spell-cost reduction, and all your spells having flash, which ends up being you drawing as many cards as you want (yes, your whole deck, if so desired), casting almost anything you want, and ultimately winning through the protection of counterspells and extra turns to attack with an ungodly large army on T3 or T4, although it's usually T5-ish (a T1 win was viable with Jeweled Lotus and Mana Crypt in the deck, but now a god-hand can only win T2; although once I put Leyline of Anticipation in the deck it can theoretically win T1 again).
Being able to cast everything at flash speed (with Heliod flipped) in response to anything else on the stack is effectively granting ultimate-control of the stack, especially when so many of your spells are free... things resolve if and when you want them to. For, if/when the stack gets big and full of action, and once your opponents run out of interaction, then Whirlwind Denial, Spell Burst (or even Forbid) let you clean up unwanted spells from the stack before you let everything else (i.e. your spells) resolve. And 90% of the time you draw 90% of your deck, if wanted, so it's not like you're playing a game of luck on how you can maybe potentially win. Albeit that luck element is still there, but instead it revolves around 1) is someone else going to win before I can? [i.e. will I have access to enough cheap ramp early on to win faster?] 2) Can I successfully cast and then flip Heliod without it getting countered or removed? And 3) will I draw enough of the right draw-cards to let Heliod explode my deck into play? In my experience, more often than not, I'm successfully popping off before anyone else (usually due to interaction stopping people), with counterspell protection in hand, and I almost always get enough card draw to get the wheels turning into a dominant wincon. And without Jeweled Lotus and Mana Crypt allowing as many T1 lockdowns, this Heliod deck will only benefit from opponents consistently having slower starts. (That being said, my group decided not to ban them.) This deck is built to play out strong and early with consistency, and it always finishes with touches of utter dominance. Sorry, no wiggle room allowed. But you have to get Heliod successfully flipped with a mass card draw spell in hand/play... maybe even consider a mulligan with an opening hand with no mass-draw card to use.
For a rundown on how a game vaguely/usually ends up going, after you cast and flip Heliod, say you tap Lore Broker to make everyone draw a card and discard, and we'll say you only have three opponents (although we normally have 5-7 at my pod's table), so you've made opponents draw three cards, reducing your spells by three generic mana. Then you cast Time Reversal for UU, drawing two mana rocks you can cast for free (cost reduced), and Stroke of Genius, among other cards. Your opponents drew 21 more cards, totalling 24, so you cast Stroke of Genius for X equals 22, drawing 22 cards. You drew more mana rocks you can cast for free, and more draw cards, counterspells, etc. You cast God-Pharaoh's Statue for free, but an opponent tries to counter it, so you respond with Spell Burst cast for only U, and then it's returned to your hand. But an opponent tries to counter that, so you cast Gilded Lotus in response. Yes, I said Gilded Lotus. They all let it resolve. You cast Prosperity for X equals 24, and everyone draws 24 cards, with your opponents now totaling 96 cards, reducing your spells by 96 generic mana. You cast Ultramarines Honour Guard with squad 2 paid 46 times for only one white mana, getting 43 Astarte Warriors that are effectively all 44/44... someone tries to counter it. You respond by casting Wandering Archaic
, and again another counterspell comes out to stop it. But then someone else responds by trying to destroy Heliod at instant speed. You respond by casting Arcane Signet. Then Coveted Jewel, and Chromatic Orrery. Then you cast an overloaded Cyclonic Rift for one blue mana. What's that...? No more counterspells? It resolves. Then you cast Whirlwind Denial and counter every opponents' remaining spells on the stack, and then all your spells resolve at will. Then you cast Time Warp to take another turn after this one, and attack all out. And usually, there's a lot more interaction, but I've always had a counterspell in hand to get the job done, or another draw spell that can find me one, all at instant/flash speed, plus extra mana rocks to cast for free to pay for everything. With Whirlwind Denial and Spell Burst, the goal is to get all your opponents' interaction out and on the stack, then once they run out you just counter it all. And again, if needed, there are plenty of "draw X cards" spells to reload your hand at instant speed with anything/everything you need to keep putting more counterspells and/or other spells on the stack to keep bullying your way through everything they toss at you. But they always run out of firepower... usually mana. Every single time. The only times my deck has lost was due to user idiocy (that's me; either making newbie mistakes learning the deck, or just being a goober stoner), or an opponent popping off before I could (my buddy's Urza deck likes to pop off T1, typically locking up the table in some way by T2 or T3). But usually, my deck lost because I was an idiot pilot, and the win was either in hand, or it was effectively in hand (I've totally blown a couple of gimmes [uggg]). I'm pretty confident that if not for user retardation, the deck should be 15-4, if not 16-3. Its 11-8 record does not correctly show how powerful the deck really has been.
Stats
12 - Counterspells (plus two Inst/Sor tutors that find them at flash speed once Heliod flips, plus Cyclonic Rift, Hycroelectric Specimien, and Wandering Archaic
do work as well, plus Sudden Substitution stops a lot of creature and/or spell-based combos in their tracks for only UU once Heliod flips)
25 - Draw Cards (18 of which make each player draw at least one card, or seven, or X equals.....? I've made my opponents draw 62 cards each before. That wasn't super smart though, as it gave them extra interaction, and we eventually had 22 spells on the stack after 4 had already resolved. Plus cards like (i.e. Teferi's Puzzle Box) that make an opponent draw a bunch of cards. Also, I'm including Scroll Rack as a "draw card", although it's technically not, but it serves the same purpose)
22 - Ramp Cards (13 reusable mana rocks, plus Lotus Petal, Training Ground for flipping Heliod, Smothering Tithe, Myriad Landscape (it's ramp), Urza's Saga, and technically Mana Drain and Finale of Revelation provide extra mana, assuming you are casting Finale of Revelation for X=10+ (which is easy to do in this deck, and untapping five lands later after flipping Heliod can be the difference between winning and losing sometimes)
The main wincons of the deck revolve around casting one or more of Space Marine Devastator (to remove artifacts and enchantments), Ultramarines Honour Guard, Gary Clone, or Finale of Glory after you've made your opponents draw a lot of cards with Heliod flipped, making them cheap to cast for a ton of (big) creature tokens, then cast Time Warp (etc) to immediately go to your next turn for a wipeout attack. (Laboratory Maniac is another easy option, as you can quickly draw your deck out if wanted.) Casting God-Pharaoh's Statue (for free) is a backbreaker for opponents who are stressing to stop you from winning (which they will, especially once they know your deck's tendency to win). Wandering Archaic
serves a similar purpose, but restricted to instants and sorceries, and if they don't pay, you copy the spell, which helps counter counterspells, or make their removal really painful to attempt using (not like we'll let it resolve anyway...). And of course Cyclonic Rift clears up debris off your road to victory (for only one blue mana).
This deck has run its paces against my pod's cEDH Urza deck, cEDH Heliod-Ballista deck, cEDH Rakdos, Lord of Riots deck, Chulane, and more, most of which sits in the 7+ power level range (9-10 = cEDH)... Sheoldred is the Achilles heel to this deck, so when sitting at the same table, you can never let Sheoldred enter play, or else you have to remove it before you can have any fun, and tbh, this deck isn't well prepared for either. Some of the counterspells can stop it from being cast, but most are geared towards stopping instant speed interaction, and removal is very thin in this deck... it's a greyhound, streamlined to win as fast as it can.