Ever since Scars of Mirrodin started being spoiled, there is one card in the set that made me moist with anticipation above and beyond all others. It's not the best card in the set, but it is the most exciting card, at least for me. It's the one card I absolutely HAD to have 4x of immediately upon release. And I did in fact accomplish this goal. I had my playset of this particular rare before I'd even managed to collect a 4x set of any of the commons!
What is this card? you ask...
Yeah. Genesis Wave. This card just screams "USE ME!" because it's one of those cards that can do really, really disgustingly broken things, OR it can do really, really hilariously awesome things. You can be a total prick by breaking this thing in half, or you can just have fun with it. It's powerful enough that you don't need to try to hard for it to be good.
That said, there are some obvious steps you would want to take if you want this to be playable. First off, you need plenty of mana. Second, you need plenty of permanents. This thing "misses" on sorceries or instants, but any permanent - land or non-land - is fair game. In a deck built around Genesis Wave, you really want as few Sorceries or Instants as possible. I suggest that you run ZERO Sorceries or Instants other than the wave itself.
That way, the only card in your deck that Genesis Wave will miss is another Genesis Wave. For this reason and others, I heavily recommend Eternal Witness as a stop gap. Say you cast your first Wave for x = 10, and somehow manage to reveal all 3 of your remaining Waves. Sucks don't it? But, should you also reveal at least one Eternal Witness, you're still in great shape. You can Wave again next turn.
But for those of you who know me, you probably have guessed that this isn't good enough for me. I don't want to cast Wave 4 turns in a row. I want to Wave 4 times in one single turn. Why? Cause I like to party, that's why. How? Well, I'll show you:
4 Llanowar Elves
4 Joraga Treespeaker
4 Lotus Cobra
3 Eternal Witness
3 Knight of the Reliquary
3 Emeria Angel
2 Rampaging Baloths
2 Primeval Titan
2 Admonition Angel
3 Khalni Heart Expedition
3 Mirari's Wake
4 Genesis Wave
3 Temple Garden
1 Gaea's Cradle
4 Misty Rainforest (sub Windswept Heath, if you got 'em)
Yes, that's a 9-post mana base. I run the singleton Glimmerpost because you never know when gaining 4-8 life might mean the difference between losing and not losing. And because this deck WILL draw hate, once your group knows what you're up to. Also, it just helps make Cloudposts that much more potent.
Anyway, 75% of this deck is Mana Engine, Wave and Witness are the "Combo Peices" and then a 10-card package of Win Conditions. (Primeval Titan pulls double duty, primarily as part of the Mana Engine, can easily moonlight as a Win Condition). So, you can easily play games were you make 34 mana buy turn 4, but have little else to do. The good thing about this deck, though, is that you don't NEED Wave to win.
I gold-fished a game moments ago where I cast a Primeval Titan on turn 3, and followed it up with a Admontion Angel AND Rampaging Baloths, both hardcast on turn 4... and that was BEFORE I attacked with the Primeval Titan, getting two more lands to trigger the Angel and the Baloth twice each, leaving me with 29 power on the board (counting an Elf and a Cobra). On turn 4. Without casting Genesis Wave. True, that's a god-hand scenario, but it can and will happen sometimes.
Usually though, you'll just accelerate until you can Wave for 12 or so, and then with a combination of Lotus Cobras, Lands coming into play, Kahlni Garden, Witness and maybe a Wake or a Titan, you should be in a position to immediately cast a second Wave, for at least another 12 to 15, then if you have enough Library left, a third Wave is not out of the question.
This begs the question: What happens if you Genesis Wave out two-thirds of your library or more and your opponent simply grins and plays Wrath of God?
Well, my good sir, you lose, that's what you do. Unfortunately, this is the drawback to this kind of all-in deck style. It wants to win big, Big, BIG and a well-timed Wrath can fuck it's shit up pretty thoroughly.
But, remember what I said, this deck CAN win without Wave, or you can at least be conservative with the Waves. I'd recommend that, if you are reasonably sure your opponent is running mass removal, you should cast your Waves for x = 6. Nothing in the deck cost above 6, so you'll be guaranteed to hit something, but you won't over-commit too badly. Then again, the first time I cast Wave for x=6, I hit the following: Misty Rainforest, Lotus Cobra, Emeria Angel, Primeval Titan, Rampaging Baloth and Admontion Angel. So even if my opponent had the Wrath, I still had one of each of the 6/6 guys left in my deck, plus two Emeria Angels. I'd say I was in okay shape if Wrath was in store.
There are a few tweaks I'd like to make. First and foremost is bumping Eternal Witness up to 4x, but one of my set is in the Big Highlander. I'm not too sure if Wake is needed, but Mirari's Wake is one of my favorite cards in the entire game of Magic, and I can't conceive of building a G/W deck that wants tons of mana, and not running Wake. Just seems wrong somehow. Khalni Heart Expedition is a bit iffy too, but so far it's been acceptable.
Anyway, I played this deck one time last night, and after resolving my first Genesis Wave, I started adding up my resulting mana, and after deducing I had somewhere around 15 mana, one of my opponents asked if I had another Wave. I said "yeah" and the whole table scooped at once. I guess no one had a Wrath that time...