-------------------------------------------------------------------------------------------------
Boarding out
-------------------------------------------------------------------------------------------------

1) Of course we should first drop tools that aren’t specific to the job before us. They don’t play enchantments/artifacts? Drop rec sage. They don’t use their graveyard as a resource, and/or in the match-up we won’t want to use OUR graveyard as a resource? Drop scooze. They play significant artifact hate/no pumps/little targeted removal/we don’t crucially need a blocker with 4 toughness? Drop skite. They don’t play forest? Drop elvish champion. They don’t threaten our life total/are rather trying to fight a resource war? Drop essence warden. All of this is fairly obvious but I think needs to be said because it’s the first step, and it opens a significant number of spots for boarded-in answers.

2) Against dedicated aggro/fast combo, we need to worry less about grinding out value or achieving card advantage. Tempo becomes the priority because these match-ups largely remain a race. We’re either playing the cards that most quickly get us to the overrun/pump win, or we’re playing the cards that most severely slow down the opponent (these vary depending on the matchup).

Therefore, against dedicated aggro/fast combo, up to 4 elvish visionaries (firstly) and the 4th kill condition (secondly – ezuri/mirror) are typically the best drops. The rationale underlying cutting the visionaries should be clear – its best value is in the battle for card advantage/attrition. This is almost totally irrelevant in these match-ups – when they kill you, you can still be holding plenty of cards in your hand. At the same time elvish visionary does nothing to slow the opponent down and has all of the structural 2-drop problems I’ve discussed in prior posts, so it’s an easy cut. My theory on cutting the 4th kill condition – the deck still functions fine on three kill conditions, and you lose more to drawing two with insufficient ramp than you do in not having one (between 4 chords/4 companies/3 copies of Ezuri, we have PLENTY of ways to find a single Ezuri). There’s also always the option to go wide and beat down on lord pumps if you don’t pull the Ezuri. We simply cannot afford to stumble, at all, and cutting the 4th kill condition marginally helps this. Definitely cut the fourth visionary before you cut the first kill condition.

3) Against grindier decks/control, we must accept that the match-up is likely to go long in the face of heavy removal/sweepers/counters/discard post-board. The other reality is that Ezuri overruns are less frequently the path to victory. Dumping everything into the board plays directly into a sweeper, so instead we’re more frequently chip-shotting damage to get to 20 while holding up collected company to bail ourselves out of disasters.

These dynamics force us to play at the opponent’s pace, on the opponent’s turf, so we need to equip ourselves to handle it. The general philosophy is that we want to keep all of your most independently powerful cards - the cards that require the least support around them to make a substantial difference in the game. This sideboarding philosophy concurrently improves the quality of our top-decks in the mid/late game.

A secondary consequence of this is that the average card’s casting cost increases. We’re looking to cut cheap, weak stuff (1 drops) for haymakers (3 drops) to hang with the grind/control builds. All subject to the restrictions of playing a 19-land deck, of course.

First on the chopping block is up to 3 heritage druids. I generally like to keep 1 in the deck as a chord target. Sometimes a window will open where heritage druid can enable some game-changing plays. If we keep 1, we keep those windows open and present more risk to the opponent. On this same rationale, I generally like to keep in 1 copy of copperhorn scout. If you run the second copy, that’s an easy cut.

If you need more space, you can once again cut the 4th kill condition, but generally I think it is correct to cut the third Ezuri before the 1st Mirror (if you run it). Ezuri is a lightning rod for targeted removal because it cannot save itself, whereas Mirror CAN save itself and the rest of the team against damage-based removal. Additionally, in these match-ups its frequently harder to get to multiples of 5 mana for Ezuri overruns. Mirror’s ability makes it a little easier to efficiently produce combat damage from a variety of board positions. Since the games go longer anyway you’re more likely to see white mana to hard cast him.

If you need even more space, cut Nettle Sentinels before you cut Mystics/Llanowar Elves. Post-board, our average casting cost increases, so these elves become indispensable in importance - they independently generate mana.

4) What not to remove in any match-up - I don't think I've ever boarded out Collected Company, Chord of Calling, Llanowar Elves, Elvish Mystic, or Elvish Archdruid. I could see boarding out archdruid in some rare circumstances, but I believe the rest of the above represents the functional core of the deck.

Based on Frank Karsten's math it looks like 33 creatures gives you a 95% to hit 2 on Company. 27 creatures has it at 85% to hit 2. So if at worst I go to 30, that probably makes me at about 90% to hit 2. That's acceptable to me.

Frank Karsten's math
http://www.channelfireball.com/articles/magic-math-how-consistent-are-spoils-of-the-vault-collected-company-and-griselbrand-in-modern/

-------------------------------------------------------------------------------------------------
More on Sideboarding
-------------------------------------------------------------------------------------------------

This deck should play like Affinity in Game 1. Come out super-fast and steal the first game more than 60% of the time. Then the script flips in Games 2 and 3. We win many more Games 2 and 3 through Plan B than Plan A - we grind out a win in aggregated combat damage rather than a lump-sum Ezuri Alpha strike.

Maindeck cards whose value improves in the average Game 2 or 3:
Horizon Canopy
Elvish Visionary
Scavenging Ooze
Collected Company

Maindeck cards whose value decreases in the average Game 2 or 3:
- Fetchlands (we need to make our land drops since our dork casualty rate skyrockets).
- Nykthos, Shrine to Nyx
- Heritage Druid (!!! Bad top deck in a long grinding game, dork casualty rate makes his activated ability worse).
- Copperhorn Scout (Bad top deck, less likely to be in position to make optimal use of his triggered ability).
- Nettle Sentinel (more useful than Heritage Druid as a 2/2 for 1, but if some number of Heritages come out, he gets worse).
- Either win condition (don't want as many copies. Go from 4 to 3.)

Chord of Calling deserves its own special conversation. If you have to chord for a game-changing 1 CMC or 2 CMC bullet in Game 2 or 3, chord of calling can be an absolute allstar. If not, it typically gets worse - since the dorks die more often, you're less able to chord for 3, sometimes it sits in your hand or you just don't want to draw multiples.