Hello and welcome back to Metagame Mentor, your weekly guide to the top decks and latest Constructed developments on the path to the Pro Tour. This past weekend, hundreds of competitors entered the Regional Championships for Japan/South Korea, South America, and East Canada, marking the first premier Pioneer events since the release of The Lost Caverns of Ixalan.

The discover mechanic enabled powerful new combo strategies, and various other new cards made an impact as well. In today's article, we'll take a closer look at the hottest new Pioneer decks from these events. But first, let me offer my congratulations to the three Regional Champions.

Congratulations to the Regional Champions!

【お知らせ】一新されたパイオニア環境が舞台となった日韓最強決定戦「チャンピオンズカップファイナル シーズン2ラウンド1」。優勝はジャンド異形化を使用した増門健太選手となりました！おめでとうございます！

⬇イベントカバレージhttps://t.co/mLBQL1k6sg#mtgjp #マジックチャンピオンズカップ pic.twitter.com/6LehetGQWZ

— マジック：ザ・ギャザリング (@mtgjp) November 26, 2023

Congratulations to Kenta Masukado, who won the Champions Cup Final (i.e., Regional Championship for Japan and South Korea) with Jund Transmogrify! In the finals, he defeated Yuya Hosokawa, playing Azorius Control. Both finalists earned an invitation to World Championship 30, held at MagicCon: Las Vegas on October 25–27, 2024.

In addition, the top 12 players who were not yet qualified for Pro Tour Murders at Karlov Manor earned an invitation to that Pro Tour, which will showcase the Pioneer format at MagicCon: Chicago on February 23–25, 2024.

Ha Pham is the master of the phoenixes and the new Canadian Regional Champion! Ha defeated 320 players and a top eight filled with Phoenix mirrors to claim the title. Congratulations Ha and best of luck at the Pro Tour and World Championships!#F2FYYZ #MTG @PlayMTG pic.twitter.com/JV41bCZImh

— Face to Face Games (@FaceToFaceGames) November 27, 2023

Congratulations to Ha Pham, who won the F2F Tour Championships (i.e., the Regional Championship for East Canada) with Grixis Phoenix, earning an invitation to World Championship 30! In addition, the top 4 players earned an invite to Pro Tour Murders at Karlov Manor. Arclight Phoenix ruled the event in Canada, with five of the Top 8 players returning 3/2 fliers from the graveyard!

Guillermo Sulimovich de Uruguay 🇺🇾 es el gran campeón del Regional Championship la 4ta ronda de la South America Magic Series. ¡FELICITACIONES AL GANADOR! Directo al Pro Tour de #MagicTheGathering #mtgsams #mtgpioneer pic.twitter.com/t7wea5JgM2

— South America Magic Series (@smagicseries) November 26, 2023

Congratulations to Guillermo Sulimovich, who won the South America Championship (i.e., the Regional Championship for South America) with the hot new Geoform deck, earning an invitation to World Championship 30. In addition, he and his opponent in the finals, Santiago Bigatti, earned an invite to Pro Tour Murders at Karlov Manor.

The Metagame and Win Rates

In total, 729 Pioneer decklists were submitted across the three Regional Championships. After fixing mislabeled archetypes, I determined the combined metagame share and the match win rates (non-mirror, non-bye, non-draw) of every archetype this past weekend. In the following table, each archetype name hyperlinks to a well-performing decklist close to the aggregate of that archetype.

The "Other" category included such deck archetypes as Jund Transmogrify, Selesnya Angels, Boros Legends, Goblins, Mono-Red Aggro, Dimir Control, Jeskai Ascendancy, Rona to Light, Jund Midrange, Sultai Soulflayer, Bant Spirits, Grixis Phoenix, Rona Lukka Combo, Rakdos Demolition, Rakdos Transmogrify, Merfolk, Dimir Oracle, Dimir Rogues, Omnath to Light, Archfiend Alteration, Selesnya Company, Golgari Midrange, Elementals, Bant Lotus Field, Boros Creativity, Izzet Transmogrify, Izzet Ensoul, Waste Not, and more.

As indicated by the arrows in the table, the metagame had changed quite a bit since the previous weekend of Pioneer Regional Championships, which took place before the release of The Lost Caverns of Ixalan. As Mono-Green Devotion and Mono-White Humans dropped in popularity, several decks that gained new cards from the new set surged ahead, as I'll cover in more detail in this article.

For most archetypes, considering the sample sizes, their match win rates were nearly indistinguishable from 50%, indicating a balanced metagame. The only exception was the new Quintorius Combo, which underperformed significantly.

The Most-Played New Cards From The Lost Caverns of Ixalan

The most-played nonland cards overall were Thoughtseize, Fable of the Mirror-Breaker, and Fatal Push—these are perennial Pioneer staples. Yet The Lost Caverns of Ixalan introduced numerous important new cards as well, including Get Lost as the fourth-most played card overall. The following table reveals the 20 most-played new-to-Pioneer cards across the decklists registered for last weekend's Regional Championships.

Get Lost is an efficient removal spell that slotted into a variety of white decks, while Trumpeting Carnosaur is an important piece of the new discover combo decks, and many other new cards found important homes as well. To see where they slotted in, let's zoom in on eight well-performing decklists that use the new cards.

Appraising Geological Appraiser

The hottest new Pioneer deck coming out of The Lost Caverns of Ixalan is based around Geological Appraiser and Eldritch Evolution. Since Eldritch Evolution is similar to Neoform, the deck has been dubbed Geoform, and it took a 8.5% share of the metagame last weekend, with Guillermo Sulimovich taking down the South American Championship. Check out Cobin Hosler's The Week that Was column on Friday to learn more about his journey! Guillermo Sulimovich's list was similar to the one used by Motohiko Nakao to make Top 8 at the Regional Championship for Japan and South Korea, showing that it's a well-tuned version of this brand new archetype.

The combo starts by resolving Geological Appraiser. You're guaranteed to discover into either Glasspool Mimic, which copies Geological Appraiser, or Eldritch Evolution, which turns the four-drop into Trumpeting Carnosaur. In both cases, you get another discover trigger and can keep the chain going. You keep discovering for a while until your board is wide enough, at which point you use Eldritch Evolution to get Doomskar Titan, give haste to all your creatures, and attack for the win. If you accidentally drew Doomskar Titan, then you can evolve Trumpeting Carnosaur into Ghalta, Stampede Tyrant and set up a lethal attack after all.

With the Treasures created by Creative Outburst and Magma Opus, the deck can consistently cast Geological Appraiser on turn three, winning the game on the spot. Ramping into Trumpeting Carnosaur or even Torrential Gearhulk will also work well as a backup plan. After sideboard against control decks, Thought Distortion shouldn't be underestimated either. To buy time for the various six-drop backup plans, split cards like Bedeck // Bedazzle provide interaction without messing up the discover chains.

The combo is powerful, yet fragile: A single piece of countermagic or creature removal can stop the chain. Cards like Damping Sphere, Roiling Vortex, Silence, Drannith Magistrate, Eidolon of Rhetoric, Hushbringer, Strict Proctor, Archon of Emeria, and so on are very effective as well, and their popularity has climbed since the Geoform deck burst onto the scene.

Some of these cards were even played in main decks. For example, at the Regional Championship for Japan and South Korea, Ryota Takeuchi earned a Pro Tour invite with main deck Silence and Kazushige Shimamura earned a Pro Tour invite with main deck Roiling Vortex. So, players who were ready for Geoform were rewarded for their foresight. Azorius Lotus Field also rose in popularity because it can leverage main deck Strict Proctor, which doubles as an answer to Geological Appraiser. Finally, the new Regional Champion, Kenta Masukado, tweaked his Jund Transmogrify list by replacing Fatal Push with Torch the Tower to answer Geological Appraiser. Moreover, he relied on Void Winnower as a Transmogrify target after sideboard, stopping all the discover creatures with even mana values. Overall, opponents were ready for Geoform, but the new strategy still performed quite well.

The Elephant in the Room

Quintorius Kand birthed an entirely new archetype similar to Geoform. Quintorius Combo decks revolve around using the planeswalker's -3 ability to discover into Clever Impersonator or Spark Double. Casting one of them from exile drains the opponent for two and gives you a new Quintorius copy to keep the chain going. Since Spark Double becomes a nonlegendary copy, you effectively create another Quintorius, flooding the battlefield with planeswalkers. If you keep adding Spark Doubles, you'll drain your opponent for four, then six, then eight, stacking up enough triggers to produce lethal on the same turn.

Trumpeting Carnosaur once again reprises its role as a backup combo piece, and the deck uses a combination of adventures, channel effects, cost reduction spells, and split cards, all with mana value six or higher, to interact with the opponent in the early turns of the game.

At 7.5% of the field, Quintorius Combo was nearly as popular as Geoform, and it's not as vulnerable to creature removal like Fiery Impulse. However, the deck performed far worse. Markus Thibeau had one of the best finishes with the deck last weekend, finishing 26th with a 9-4 record in Canada, but he still came a few wins short of a Pro Tour invite. Compared to Geological Appraiser, Quintorius Kand is a full turn slower, which is a substantial downside. Perhaps Quintorius Combo would be more viable if typical interaction was geared more against creatures, but commonly played removal spells like Bonecrusher Giant, Get Lost, Torch the Tower can all remove the planeswalker in response to a discover activation, and Spell Pierce works as well. Although it remains a powerful one-card combo, it's relatively easy to interact with.

Exploring Amalia Benavides Aguirre

Besides the new discover combos, The Lost Caverns of Ixalan also introduced a novel explore combo. Santiago Bigatti finished second at the South America Championship with Amalia Benavides Aguirre, which can produce lethal damage on turn three if you follow up with Wildgrowth Walker and a life gain effect or explore ability.

Specifically, if you curve turn two Amalia Benavides Aguirre into turn three Wildgrowth Walker and start the chain, for example by exploring with Cenote Scout or gaining life with Lunarch Veteran, then Amalia explores, which triggers Wildgrowth Walker, which triggers Amalia, and so on. Eventually, Amalia reaches twenty power, all other creatures are destroyed, the loop ends, and she'll swing in for lethal.

All combo pieces can be found with Collected Company, and Return to the Ranks provides protection against spot removal. The end result is a sweet new creature-based combo deck in Pioneer.

Get Lost in Azorius Control

Get Lost was the most-played new cards from The Lost Caverns of Ixalan, and it found its way into a variety of decks, including Azorius Lotus Field, Azorius Control, Azorius Spirits, and Mono-White Humans. For example, Yuya Hosokawa earned a World Championship invite with the Azorius Control list shown above, featuring four copies of Get Lost. The deck also featured four copies of Restless Anchorage as a new card, adding a win condition to the mana base.

Get Lost is similar to Fateful Absence, which has been a popular removal spell in Pioneer, but two Map tokens represents a smaller drawback than a single Clue token. Especially when you can use another removal spell in response to a Map activation to take out the targeted creature, you can minimize the benefit you give the opponent. In addition, the ability to destroy enchantments like Leyline Binding grants more flexibility. All in all, Get Lost has quickly become a Pioneer staple.

Warden of the Inner Sky in Boros Convoke

Two Boros Convoke players made the Top 8 of the Regional Championship for Japan and South Korea, and both of them used Warden of the Inner Sky in their main deck. Replacing Legion's Landing or other one-drops, Warden of the Inner Sky is a substantial upgrade for the deck because it has excellent synergy with Gleeful Demolition and Venerated Loxodon.

For example, if you lead with Thraben Inspector on turn one, followed by Warden of the Inner Sky and Gleeful Demolition on turn two, then you can already get it up to a 3/4 by turn two, allowing you to attack with flying and vigilance as early as turn three. In the process, you even get to scry towards key cards. Alternatively, since it doesn't care where the +1/+1 counters come from, tapping Warden of the Inner Sky to convoke Venerated Loxodon also gets you closer to the flying and vigilance bonus. Boros Convoke remains a formidable strategy in Pioneer, especially with his new addition.

Bitter Triumph in Grixis Phoenix

Bitter Triumph is an efficient removal spell that can deal with Geological Appraiser, Quintorius Kand, or any other creature or planeswalker for only two mana. Many Rakdos Midrange and Rakdos Sacrifice players have added a few copies, but the new instant is at its best in decks that can turn the discard into an upside. For example, Ryota Takeuchi earned a Pro Tour invite with Abzan Greasefang featuring 3 Bitter Triumphs, where it acts as a discard outlet for Parhelion II.

But the most impressive home for the card was in the Grixis Phoenix deck that won the Regional Championship in Canada. Ha Pham used it as a more flexible version of Lightning Axe and took down the trophy. His list, essentially a blue-black control deck with a few red lands to hardcast Arclight Phoenix if needed, used the card as a flexible removal spell that can put Arclight Phoenix into the graveyard if convenient. It's an innovative brew that makes excellent use of the new removal spell.

Sunken Citadel in Azorius Lotus Field

Although Sunken Citadel was not a universal inclusion in Azorius Lotus Field, there were several players who used the card to good effect in the deck. For example, Julio Bejarano Espejo used the card to make the Top 4 at the South American Championship.

In this list, Sunken Citadel is a mana fixer that taps for two when activating Thespian's Stage, Castle Ardenvale, Castle Vantress, Hall of Storm Giants, Azcanta, the Sunken Ruin, or Restless Anchorage. Even the channel abilities of Eiganjo, Seat of the Empire and Otawara, Soaring City count as a land source. Extra mana is never bad, and since the deck doesn't have any one-mana spells, it's almost free to play a tapped land on turn one. At the very least, it's a sweet new option for the archetype.

Inti, Seneschal of the Sun in Boros Legends

The final new cards that I wanted to highlight are a pair of legends: Inti, Seneschal of the Sun and Anim Pakal, Thousandth Moon. Both of them are good fits for an aggro strategy that wants to get additional benefits from attacking, and they synergize well together—if Inti puts an extra +1/+1 counter onto Anim Pakal, then you'll create an additional Gnome as a result.

More importantly, they enabled a critical mass of powerful legends in red and white, unlocking Plaza of Heroes and Mox Amber as consistent payoffs. With Mox Amber, you can ramp into Adeline, Resplendent Cathar or Anim Pakal, Thousandth Moon as early as turn two. With an ideal draw involving Embercleave, you could even present lethal damage on turn three!

Several players brought Boros Legends to their Regional Championships, and Max Honiball's 8-5 record shows that it holds promise as a sweet new archetype.

Looking Ahead

There was a lot of innovation at last weekend's Regional Championships, and The Lost Caverns of Ixalan has shaken up the Pioneer metagame. It will surely have a big impact on the final Pioneer Regional Championship of the cycle, held on December 16–17 in Atlanta, Georgia, U.S.A. Don't miss the livestream on Twitch or all decklists on Melee!

As announced on WeeklyMTG, there will be a banlist update this Monday, December 4, with changes to Pioneer and Modern.