Over the past few days, there have been a multitude of major Pioneer events. Over the weekend, there were Regional Championships in Canada, Japan and South America. On Monday and Tuesday, there were multiple Magic Online Pioneer Last Chance events, where players that go undefeated through five rounds earn their chance to compete in a Showcase Qualifier. Unsurprisingly, for these events with lots on the line, top tier archetypes were heavily represented.
Geological Appraiser


At the beginning of combat on your turn, if you've cast three or more instant and sorcery spells this turn, return this card from your graveyard to the battlefield.
in their decks!
Interestingly, though, while the winner of the Regional Championship was utilizing Arclight Phoenix, they weren’t doing so in the traditional Izzet shell. Instead, they were playing a unique Grixis Phoenix build, primarily Dimir-focused. Then, multiple players went undefeated in the Pioneer Last Chance events with identical decklists! It’s unusual to see brews at high-level tournaments have this level of success right away, but this deck has a lot going for it.
The Value of Adding Black

With the decent level of success that Izzet Phoenix has been having in the format since the introduction of Picklock Prankster and Sleight of Hand, it may seem a bit strange for the deck to go through further adaptations. However, honing on a Dimir-centric shell makes a lot of sense in the current metagame. The biggest addition this deck gains is definitely
Thoughtseize

Even if Discover combo sees a ban on December 4, which is quite likely, getting to nab Venerated Loxodon from Boros Convoke or Sylvan Scrying from
Lotus Field

This land enters tapped.
When this land enters, sacrifice two lands.
{T}: Add three mana of any one color.
combo can be game-changing. Izzet Phoenix does get to make use of cards like
Spell Pierce

Of course, running Thoughtseize has been an option for a while. So has replacing
Fiery Impulse

Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, Fiery Impulse deals 3 damage instead.
with
Fatal Push

Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent left the battlefield under your control this turn.
. What helped push this decision to move to black over the edge was the release of Bitter Triumph in The Lost Caverns of Ixalan. Bitter Triumph fills a very similar role to Lightning Axe, as it adds both a removal spell for big Creatures and an extra discard outlet for Arclight Phoenix in one. Bitter Triumph is even more flexible, since you can choose to pay three life and not discard any cards when it’s convenient to do so. It also helps kill Planeswalkers that would otherwise be difficult to deal with.
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Maintaining Izzet Phoenix’s Core Gameplan

All of the non-black cards in the deck are pretty standard inclusions for the Phoenix archetype. Cantrips, like Opt and Consider, help in a bunch of ways.
First, they are cheap spells to cast that replace themselves, helping you chain spells together to bring back Arclight Phoenixes. Second, they help dig for interaction. Finally, and most importantly, they fuel the best card in the deck: Treasure Cruise.
Treasure Cruise is an absurd MTG card that’s banned in Modern and Legacy for a reason. The key to making it strong in Pioneer is fueling Delve without being able to use Fetchlands. These cheap cantrips alongside Picklock Prankster and Ledger Shredder all but guarantee your ability to cast Treasure Cruise for cheap and keep the card advantage flowing. Ledger Shredder is a solid threat on its own as well, threatening to grow over time and discard copies of Arclight Phoenix that could otherwise get stuck in your hand.
This deck may be labeled Grixis Phoenix, but it truly is a Dimir deck that happens to play four copies of Arclight Phoenix. The manabase is entirely Dimir colored outside of two copies of
Steam Vents

As this land enters, you may pay 2 life. If you don't, it enters tapped.
. Steam Vents is utilized solely as a way to hard cast Arclight Phoenix when needed, which can be essential in the face of graveyard hate.
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Helping in the Mirror Match

As mentioned, the addition of Thoughtseize helps a ton against opposing combo decks, so in a vield dominated by Discover combo, playing black makes a ton of sense. Even with a likely
Geological Appraiser


Whenever you draw a card, you gain 2 life.
Whenever an opponent draws a card, they lose 2 life.
.
As a 4/5, killing it isn’t always easy for Izzet Phoenix to do. They essentially need Lightning Axe or multiple removal spells. Not to mention you may be able to clear the way with Thoughtseize. Additionally, Sheoldred is a nightmare for Phoenix decks if they can’t kill it immediately, since a huge portion of the Phoenix deck is dedicated to drawing cards.
If that weren’t enough, you essentially get to free-roll Cling to Dust as a permanent answer to opposing copies of Arclight Phoenix, as well as utilize Go Blank out of the sideboard to keep your opponent’s Treasure Cruises in check. Thoughtseize can prevent you from getting blown out by Narset’s Reversal when you go to cast your own Treasure Cruises, which will ultimately pull you ahead.
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Strengths and Weaknesses

As strong as adding black is for the Phoenix deck in the current metagame, there are some matchups where this is a downside. One of the biggest things you lose as a Dimir deck compared to Izzet is the ability to run Artifact hate out of the sideboard. Brotherhood’s End and
Abrade

• Abrade deals 3 damage to target creature.
• Destroy target artifact.
were great cards against Rakdos sacrifice, as well as excellent answers to
Unlicensed Hearse

Unlicensed Hearse's power and toughness are each equal to the number of cards exiled with it.
Crew 2
. Hearse is a reliable way to both keep Treasure Cruise and Arclight Phoenix in check that the Dimir deck has a hard time dealing with.
Speaking of graveyard hate, the Dimir version also lacks Crackling Drake. Crackling Drake was a solid sideboard card that could win the game through
Rest in Peace

If a card or token would be put into a graveyard from anywhere, exile it instead.
out of decks like Azorius control or Spirits. Between the minimal number of red sources needed to hard cast Arclight Phoenix and the lack of extra win conditions out of the sideboard, this deck definitely has a harder time beating graveyard hate when it hits the board.
Still, having access to Thoughtseize means that, in many cases, it can be hard for your opponent to stick a piece of graveyard hate in the first place. The addition of Bitter Triumph gives you a much better chance at beating resolved Planeswalkers, such as Teferi, Hero of Dominaria.
It’s unclear exactly what will get banned or unbanned on Monday, but the focus from the WeeklyMTG ban discussion yesterday was primarily directed towards Discover combo and mono-green Devotion. This Dimir-centric Phoenix deck is extremely strong and could theoretically be getting even stronger after the ban announcement. If you enjoy playing Pioneer, definitely make sure this deck is on your radar moving forward.
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