Shadows over Innistrad is going to be madness, and I'm not saying that just to hit my quota of madness jokes (though I do have one). I'm a huge fan of returning to places we've been before, and Innistrad being one of my all-time favorites doesn't hurt in the slightest. With the return to Innistrad also comes a return of one of the most unique mechanics we've ever seen: madness. This originally appeared in Odyssey block, and came back for a second go-round in Planar Chaos and Future Sight. I greatly enjoyed playing with it every time and see no reason why it can't charm me a third time.
Let's take a look at one of the simpler cards with madness.
Cards with madness each have an alternate casting cost that you can only use if you discard them, which opens the door to a ton of interesting play situations. With Just the Wind, it's relatively straightforward (well, as straightforward as madness cards get). You can cast the card for 1U as an instant, or you can find a way to discard it, in which case it only costs U. You may be thinking that all you accomplished was saving one mana, but there's much more to madness than that. What are the implications of madness?
Looking closer at Just the Wind, it turns out that it secretly doesn't cost you a card if you discard it to pay a cost. Imagine for a second that you've activated Jace, Vryn's Prodigy. Besides feeling good purely about that fact, think about discarding Just the Wind and paying its madness cost. All of a sudden you have a bounce spell that costs U and turns Jace's ability into tap: draw a card. Any time you discard a madness card for value, you essentially draw a card, because you get to have your cake and eat it too. Whatever you discarded for does its thing, and your madness card works as intended.
Additionally, madness tends to save you mana. A 4/3 haste for five isn't groundbreaking, but make it three mana and it becomes much more interesting. By building your deck so that you have plenty of ways to discard (more on this later), you can routinely play cards for their madness cost and end up with a bunch of undercosted threats that are likely giving you card advantage as well.
Flashes of Brilliance
Another feature of madness is that it lets you play the card whenever you discard it, which means that you can play creatures or sorceries at any time. If you have an instant-speed way to discard, all your madness cards essentially have flash, and your opponent has to be on the lookout for giant creatures jumping out during combat or at the end of their turn. Incorrigible Youths has haste, so it's not the best candidate, but you can safely assume that there will be plenty of non-hasty madness creatures to slam during your opponent's turn.
Basking in Former Glory
One of the coolest things about madness is how much it impacts deck building. It's clearly a powerful ability, but you need to take steps to harness the madness, as it were. For that, let's take a trip back to the first time madness appeared.
Dave Humpherys (Pro Tour Hall of Famer and R&D member) took the following list to the Top 4 in the 2003 Magic: The Gathering World Championship.
This was one of the most-feared decks of its era, and even won Ken Ho a Pro Tour (with Tarnished Citadel in his deck, which is quite the card). Looking at this deck can give us a sense of the components needed when trying to build a madness deck post-Innistrad. They fall into a couple categories:
Cards with Madness
Well, this isn't complicated. To build a madness deck, you should include cards with madness. Ideally you want ones that offer significant mana savings, but any powerful card with madness is an option.
Ways to discard let you play your madness cards for their insanely cheap costs, which is really the whole point of the exercise. The two examples I used also demonstrate different approaches to discard outlets. The first, Geralf's Masterpiece, is a card where you discard to get value, so paying for that discard with madness cards is a way to generate card advantage. The second, Ravenous Bloodseeker, is a vessel for discarding, and doesn't generate intrinsic advantage with its ability. Note that Bloodseeker is free and Masterpiece costs mana, so there are different advantages to each one.
Looking at the green-blue madness deck, you have Careful Study as a way to get value from discarding, and Aquamoeba as a card that mainly just gives you a way to discard for zero mana. Having a good mix of each is important, and when you can find cards that do both (cough Jace cough), you should be thrilled.
One funny thing I wanted to note is that the presence of Reality Smasher gives you bonus madness outlets. Your opponent playing one of these lets you target it and discard, which is pretty cool. Smasher is still a great card, but adding it to your deck does carry some new risks once the shadows rise.
This is a broad category, and I'm not saying you should play all three of these examples in the same deck (though that does look like a spicy brew). These are all cards that interact with the graveyard in some way, and as such are a natural fit for a madness deck. Odyssey had flashback cards like Roar of the Wurm, and we have access to variety of different cards that care about the graveyard. Both Kozilek's Return and World Breaker come back, and Dark-Dwellers generally just likes to see a well-stocked graveyard. Funnily enough, Jace, Vryn's Prodigy is also on this list. What are the odds?
Stitching It All Together
From what we've seen so far, a madness deck is brewing. Once we get to see more of what Shadows over Innistrad has to offer, we can get a clearer picture of just how crazy madness is going to be. I'm hoping for a wide selection of sweet madness cards and madness enablers, and soon all of that will be revealed.