With Gatecrash Limited season coming to a close, I want to go over some of the things that really made the Draft format unique, especially compared to Return to Ravnica. Looking forward, the ways these differences contrast the two sets will likely greatly shape full block Draft.
The Guild System
While Return to Ravnica and Gatecrash employed the same five guild setup, the end result was significantly different between the two.
Gatecrash Draft was highly delineated by guilds. There was an occasional splash or Verdant Haven deck, but that was more of the exception than the norm. The multicolored cards were often significantly more powerful than the mono-colored cards, with many being most effective in the early game. To name a few examples of this: Wojek Halberdiers; Drakewing Krasis; Shambleshark; Deathcult Rogue; and Truefire Paladin.
As a result, you needed rock solid mana to make your cards good. Splashing most gold cards wasn't reasonable because by the time you had the mana to cast them they were dead, and the best mono-colored cards were either early game cards (Daring Skyjek; Cloudfin Raptor) or unsplashable (Grisly Spectacle; Homing Lightning). The extort mechanic also punished splashes by demanding extra Orzhov guild mana that a splash land couldn't produce, especially in a non-Orzhov trio like Naya or BUG. Moving further out, the speed of the format punished splashing. You couldn't Time Walk yourself for a Guildgate on turn 3 or miss your two-drop due to bad mana without dying.
Return to Ravnica was a lot more forgiving on a lot of these measures. The format was much slower with fewer two-drops and fewer ways to punish 2/2s, meaning your Guildgate turn was easily forgivable. Tapping out for a Gatecreeper Vine or Axebane Guardian early wasn't the same death sentence as tapping out for a Prophetic Prism. Playing your Hussar Patrol on turn 5 instead of turn 4 was maybe three damage different, not six or nine. There were powerful commons to splash that were still fine later in the game, the keynote example of this being Augur Spree for multicolored cards and Stab Wound for mono-colored ones. The mechanics weren't specific to colors of mana any more than the cards they were already on.
There was also more generic fixing (three versus two), allowing you to stay open on your splash. A Gatecreeper Vine fixed for Stab Wound or Dramatic Rescue in Selesnya and Augur Spree or Common Bond in Golgari depending on what came along in your draft. An early Guildgate in Gatecrash would have to match the color of your splash card, often leading to Gruul Guildgates for your Muggings and Dimir Guildgates for your Dinrova Horrors in Simic. Many decks in this format were three colors, if not the majority of decks.
In full block Draft, being two colors seems quite difficult. Getting only one and a half packs of multicolored commons instead of three is a big loss (the half is due to Dragon's Maze's multicolored slots being 1/10 for each guild instead of 1/5). Assuming everything works out and your guild is open, it's somewhere between fighting the player on your left for your guild and fighting the player on your right for it in single set Draft. You will need a third color somewhere in most decks. Some of these cards will be the ones from Gatecrash, so your mana will have to be appropriately spread.
What does this mean for fixing and mana costs?
In a three-color deck, you will either have two guilds in pack 2 (Gatecrash) or pack 3 (Return to Ravnica). The pack where you get two guilds of fixing is also the pack you get two guilds of multicolored cards. Long story short, if you are aiming to play the powerful cards from both guilds, your mana won't be great. There just aren't enough picks to get Daring Skyjek, Wojek Halberdiers, Kingpin's Pet, and the appropriate fixing from one pack of cards. Obviously, you will be able to plan around any Gates you get in Dragon's Maze packs, but this seems to imply one main option.
You want to be able to sacrifice a guild of multicolored playables for a guild of fixing. I would lean towards a guild with few common multicolored cards that you want to draft early being your primary source of Gates and Keyrunes. This also avoids the issue of your fixing exactly lining up with your multicolored spells in three colors. Boros Guildgate plus Forest does not cast Wojek Halberdiers despite making all your colors, but Selesnya Guildgate plus Mountain or Gruul Guildgate plus Plains do.
Rakdos, Dimir, Gruul, and Izzet would be my frontrunners for the "shafted" guild, while all of the white guilds (Selesnya, Azorius, Orzhov, and Boros) are poorly suited for this since they are three very playable commons deep between gold and hybrid. Golgari is somewhat light on really good cards but has three decent commons, and Simic has two absurdly good cards and two unplayable ones. Assuming you bridge your fixing guild with a good or average one in the same set, this setup lends itself to G/B/R, W/U/B, BUG, W/R/G, RUG, and W/U/R (but not U/B/R as that doubles up on "bad" guilds). W/U/B and W/G/R seem especially strong because they connect two of the deep guilds (Azorius and Orzhov or Selesnya and Boros).
One warning: this may backfire on a meta level. If the best cards in the "bad" guilds are fixers, they may dry up faster than you expect. Going W/G/B or W/U/G puts you super deep on playables and fixing across the board, which should hopefully ensure you get enough of each. On the flip side, U/B/R is going to need some serious help in Dragon's Maze or your higher rarities to be playable, and W/R/B gives you a quite bad last pack similar to W/G/B or W/G/R in the original Ravnica block in return for the two best guilds pack 2. That said, turn 1 Rakdos Guildgate lets you cast both Wojek Halberdiers and Kingpin's Pet on time with a Plains, allowing your fixing to really line up with your aggressive curve.
Green decks might be able to ignore all of this and go real crazy. Gatecreeper Vine does a lot more when there are six double off-color Gates to fetch instead of just three.
One minor note is that cards that cost double of a single color to cast get much worse. Assembling a mana base with seven sources of your colors is reasonable, but getting the nine sources needed to really support Sunspire Griffin on turn 3 is rough. Even the two base colors plus a splash model isn't going to crack eight sources on the main colors without four or more dual lands. Korozda Monitor was already not great, and now it's almost not castable. For those interested, there's a slight math edge (drawing two copies of an eight-of is less likely than one of an eight-of and one of another eight-of) but the real bias is in mulliganing. Having all of your colors is a likely guideline for keeping a hand, and two lands of one specific type is not reliable under those conditions.
Signals and draft fluidity will also be much higher than in Gatecrash. Finding the open guild was the big thing in that format, but abandoning a non-open guild still means you can play about two-thirds of the cards you drafted assuming a one-color swap. In Gatecrash, switching from a cut guild meant losing about two-thirds of your playable cards. Fighting over a single guild with a neighbor seems perfectly fine if it's in a double-up pack for the person downstream.
For example, a W/G/R player being passed to by a W/R/B player for the Gatecrash pack still has access to a full Gruul guild pack two despite sharing two colors with their neighbor. The above two-thirds figure also assumes you can't just splash the forth color for the card if it's good enough, which should be debatable in many trios and commonplace in green.
The key toughness point in Gatecrash was 2/3. Sage's Row Denizen brick walled all of the two-drops bar the top tier options of Daring Skyjek and Wojek Halberdiers. The two power was a big deal as well, preventing a couple 2/2s from repeatedly chipping away at your life total without some extra help. You couldn't get solid brick walls that killed guys while not dying on blocks until five mana with Horror of the Dim, Nav Squad Commandos, and Towering Thunderfist.
The key toughness point in Return to Ravnica was 2/4. Centaur tokens and the key Rakdos unleash creatures (Dead Reveler, Splatter Thug, Gore-House Chainwalker) all were bricked by the fourth point of toughness, while most of the random two-drops died to the two power. Hussar Patrol, Towering Indrik, and Armory Guard held the fort for a long time. Golgari Longlegs was literally big game as it ran over any one of these guys without assistance.
What does this mean going forward?
Quite a few of the premier commons from Gatecrash Draft will match up poorly against some of the solid ones from Return to Ravnica. Wojek Halberdiers versus Hussar Patrol, fight. It seems like Return to Ravnica will win this round on level one. As a result, the evasive creatures that were too slow to reach their full potential in Gatecrash Draft, namely Deathcult Rogue, will gain a lot of value. The next level up is that Giant Growths will be very important if you are attacking. Fortunately, Gruul has an abundance of those effects and chains well into the other aggressive guilds. W/G/R gets Selesnya and Boros, both known for aggro shells with access to Common Bond, and G/R/B gets Rakdos and unleash to play the bulkier aggro role.
Assuming the fights are more 2/2 and 3/2 versus 2/4 than the Gatecrash standard of 3/2 or 3/1 versus 3/4 or 3/5, Skinbrand Goblin looks like a card that gains significantly. Warmind Infantry gains even more on Ember Beast because 4/3 is the exact right size to break through a Hussar Patrol. Drudge Beetle actually trades for things now. On the flip side, tricks like Shielded Passage that break trades but don't break blocks will go down in value. Cobblebrute will be facing down more potential 2/2 blockers and will no longer just jam into similarly costed 2/Xs that trade for it. Stonefare Crocodile and Selesnya Sentry will be even more embarrassing than before since they trade down the curve on top of getting brick walled.
Just for the record, while it looks like the format will be less aggressive than Gatecrash, that doesn't mean it will be slow. Rakdos and Izzet sported some awesome aggro decks in straight Return to Ravnica Draft, and with the addition of the more powerful aggressive cards from Gatecrash, there will be more games where they draw the starts needed to apply pressure early.
One thing I constantly extolled about Gatecrash Limited was the integration of the rares. While there were many quite powerful ones (Obzedat, Ghost Council; Aurelia's Fury; and Boros Reckoner to name a few), they interacted on the same axis as most of the other cards. They were just creatures that brawled, good removal spells, or similar. You could beat them in a normal game of Magic without your own bomb rare or an immediate answer. Sure, a Clan Defiance for five with three targets was game over and you couldn't always beat an Obzedat, but you could try without it being a complete joke.
Return to Ravnica was the polar opposite. First off, the removal was significantly worse. Answering an in-play rare sometimes just wasn't a thing. The format was worse at racing them. Your opponent got to six mana for their Niv-Mizzet, Dracogenius 95% of the time. Finally, some of the rares just did things that didn't line up with how the format played out. Battling 3/3 versus 2/4 fights and gaining edges with card advantage and fliers? Pack Rat, good game. What does your removal destroy? I don't think it says enchantment or 4/4 creatures. Thanks Collective Blessing.
What does this mean for draft planning?
First of all, being open for bomb rares going into pack 3 will be a nice plus. Obviously, you can't move in on a Niv-Mizzet from it being off-guild, but having a fixer to mise a Collective Blessing is reasonable. You can't rely on this and I haven't gone through to break down the easy to splash ones and what color pairings want to look for this, but it's always reasonable to consider. The good news is that the really obnoxious ones will be opened much less and as such run in far fewer drafts. Only one out of every fifteen drafts will have a Pack Rat as opposed to one out of five.
The note I made about removal quality between the sets likely means you are going to have to make tough choices pack 2 between your best gold creature and that Grisly Salvage. Without full knowledge of the third set, it's impossible to say which is right, but it's something to be aware of when starting the format.
The Gatecrash bomb rares will likely get better in full block Draft. Without the aggression and removal power levels of that format to balance them, they will have more room to take over games.
Gatecrash Draft had minimal card advantage. Outside of Purge the Profane, you basically needed a cipher spell. Urban Evolution was quite slow and off-theme for its guild, and Bane Alley Broker was amazing despite not actually providing raw card advantage most of the time.
Return to Ravnica Draft had quite a bit of card advantage. Populate tricks led to plenty of two for ones, scavenge was about half a card of value on a ton of playables, Mind Rot was reasonable, and most blue decks could find an Inspiration if not a Thoughtflare.
Populate gets significantly worse. Only three non-rares make tokens larger than Knights, and all of them are uncommon (Miming Slime; Urbis Protector; and Rapid Hybridization). Scavenge is still good if not better since it appears small sizing buffs will be more important. Urban Evolution gets more powerful in a likely slower format, and cipher more relevant as smaller evasive creatures get better.
Overall, I expect full block Draft to be closer to Return to Ravnica Draft in terms of card advantage. Getting two for oned is not a giant disaster like it was in Gatecrash, but you can lose to an accumulation of it.
There is always the chance that Dragon's Maze is absurdly powerful and the Draft format revolves solely around it (see: Alara Reborn or New Phyrexia). At the very least, I would not be surprised if one of these predictions is immediately laughed at by me when I first look at the set. That said, with only Standard events between now and the set release, there's no reason not to look for a head start on the full block Draft format.