Yeah I know many similar rainbows already exist, but since I made an account on this forum finally, might as well share my version.
I've been using this for months for PvPing, and the deck basically received only 2 changes with introduction of new cards over the time. It combines speed with some perma and creature control + has a pretty decent chance to hit Elemental Mastery for a speed deck.
Here's the deck, and I'll explain reasoning for cards:
Hover over cards for details, click for permalink
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6x
Supernova - standard cards with mark of entropy. With those, you dont rely much on towers (my version only has 5 of them). If there was a way to play Supernovas on the first turn without towers, I'd probably remove them. However, you DO need them to make things faster (generating quanta for supernova on first/second turn is what kicks off the deck).
Creatures - most of those are pretty standard, trying to optimize quanta usage. Your weakest card here is Giant Frog, and with low cost is the perfect candidate for testing the waters and trying to draw out some creature control card.
Creature control - Liquid Shadow and 2 Thunderbolts. Those are there to make sure you dont get eaten or outrushed. Early Oty is a pain, 3 creature control cards make it more likely to draw something to keep those down.
Perma control - Explosion and Steal. 2 perma control cards are usually more than enough to destroy shields, SoGs, Hourglasses or weapons, whatever gets in your way of quick destruction. You need to have some knowledge here to know what to expect, so you dont waste those on weapon and SoG just to get locked down by chained shields.
Discord / Black Hole - Discord destroys mono/duo decks if you manage to draw it early. I saw too many rage-quits after drawing out this beauty. It also has fantastic synergy with Black Hole card - spread out their quanta, then suck it out for some outstanding healing. Black Hole also destroys pillarless rush decks, it slows your opponent down, it gives EM if used before the final blow. Learning to time this card right yields great results.
Unstoppable - Card that helps end things when your opponent finally manages to lay down a shield and gain control. Against rush decks, its a minor buff card. Whats not to like?
Light quanta cards - I was thorn up for a long time here, testing lots of versions. Finally I decided to go with both Blessing and Mirror shield.
Although another creature card instead of Blessing would probably add more damage overall, Blessing is exteremly useful in various situations. It helps your Lava Destroyer survive his first turn against some creature control, it helps many creatures against Oty, it gives great damage when diving with Wyrm...
Mirror shield is often overlooked shield. Its debatable should rush decks even waste time on defence. Well, some shield helps with score/money/EM. What is important to me is to not have my shield used against me (ie stolen) to slow me down. Mirror shield is untargetable, and it reflects spell damage, which is pretty awesome when against those boring fire decks. This basically rounds up the whole deck having an answer to practically everything your opponent throws at you.
Hourglass - I used to run two of those, really not needed. One is enough to speed things up, and even if you dont draw it early, you're fine. It takes 3 supernovas to set this thing up and use it once (1 time quanta is needed to evolve graboid). Having two of them clogging your starting hand is worse than not drawing hourglass at all till end game.
Liquid Shadow - This card is here because I just love it! Offensively, you want to use it on creatures like Oty, Druid etc where it works like a lobotomizer. Its good against Lava Golem too if placed on the first round.
Defensively, I like to use it on the few last turns on my first (bigger) creature (blessed Shrieker for example) for some healing and possible EM.
And there it is. Speed deck with decent EM percentage, well rounded with different types of control, damage and healing. It works great in PVP and for farming T50.