Everyone seems to take for granted that a Trix deck should run 4 Duress, but I'm not convinced. Here's what I think:
Pyro/REB: same 1 casting cost, but performs better against my worst matchup, draw-go, because Duress will likely take only one of three counters, while Pyroblast effectively neutralizes them all because, cast reactively, it destroys the counter AND the mana to cast it. Also it can be used in certain situations to destroy the Illusions when you face an opponent that can actually upkeep it for a while.
Misdirection: works almost like Force of Will, stripping opposing counter power. By the time you cast Illusions it could even be preferable to Misdirect a Disenchant (to the Necro) as opposed to Forcing it because at that point you'll already have drawn enough with the Necro and want to resume the normal draw step. Many people run 1-2 copies of this card, but I am leaning to 4.
Downside: Both fail to deal with Seal of Cleansing. It might be worth sideboarding Duress or Hoodwink or both. My main argument is that there are essentially 8 cards (Force and Consult) available to deal with this from your opening hand.
Any thoughts?
Duress can grab the opposing Necro or anti-Necro card first turn?
...and more often than not pyroblast can't be used to protect the casting of necro...unless you get red mana source out and have 4 sources in play.
Both of the cards you suggested may strenghten the deck against draw-go but make it weaker against anything (well - almost) else. Depends on your metagame ofcourse but I wouldn't make them a new "standard"
Ofcourse, I'm not a trix player so don't take these as a fact. Just reasoning...
Duress also lets you know when it is safe to attempt to go off. It not only takes acounter, it lets you know if there's backup and wait for more help. Pyroblast would just lose the counter war instead.
Duress can also strip disenchant/seal. Pyro s may xome in game2, but even then duress stays in.
I really think 4 Duress is a must. In the mirror matchup, it's huge. It is also the card that allows trix to win 30-40% against decks that are filled with trix hate. In order to win, a triz player needs to get necro on the table before his life total has dipped too far and preferably before his opponent has played a seal or something else nasty. Duress helps this a lot. It's also a fair card after necro--if you have an extra mana, keep a duress in your hand to clear out threats. Depending on your metagame, a couple maindeck pyros can be good, but they are in addition to the duresses.
Misdirection is so-so--good but not at the expense of better cards. The deck just doesn't have room for more than a couple. It doesn't stop seal of cleansing or tranquil grove, which are all over (4 maindeck seals is fairly common.) Force of will can stop seal, but you'd always rather save your forces if you can deal with threats another way. If you don't have necro or another search spell in hand, it sucks bigtime to have to burn a consult and a third of your deck for a force (or a blue card to go with a force) to deal with a must-counter. If you have to counter two spells before necro, it is somewhat unlikely that you will be able to force/misdirect both of them (have force + misdirection + 2 blue cards).
The other posts made good points as well--mana issues casting necro w/ pyro backup, the peace of mind you get from knowing what's in your opponent's hand, etc.
If you playtest a lot with/without duress (which I'd encourage you to do if you have the time and partners willing to play a lot against trix), you'll come to similar conclusions. A matchup like PT junk--they play 4 duress, 4 consults, and four seal of cleansings and cheap fat--goes from a somewhat poor matchup to to an auto-loss without duress. Duress is great against replenish, survival (all versions), stasis, fish, drawgo. Even against sligh, it's nice. You can steal their fireblast (4 life=4 more cards to look at), and be able to make an informed decision when you decide how low you can afford to necro. After sideboarding, duress shines bigtime. There are lots of nasty, cheap non-creature permanent spells (people have learned that trix kills lyrists easily) that people will bring in against you that you really can't let hit the table.
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