Magic: The Gathering's latest Standard set, Dungeons & Dragons: Adventures in the Forgotten Realms, replaced the core set release slot for 2021. In a recent Wizards of the Coast article, D&D-esign, Part 1, Mark Rosewater describes Forgotten Realms as a core set-plus since it incorporates new mechanics, including venturing into dungeons and rolling a d20. Typically, modern-era core sets contain evergreen mechanics such as trample, vigilance, flying, etc. 

Players are experiencing the new mechanics of Forgotten Realms digitally through Magic: The Gathering Arena and Magic Online. On July 23rd, Forgotten Realms will officially release in paper form. While players anxiously await sleeving Forgotten Realms cards into decks, price spikes are occurring for several synergistic cards.

Aluren

Acererak the Archlich is one of the more interesting mythic rares in Forgotten Realms. For three mana, you get a 5/5 legendary Zombie Wizard with the ability to create 2/2 Zombie creature tokens. However, there is a catch to keep Acererak the Archlich on the battlefield. If you haven't completed the dungeon called Tomb of Annihilation, you must return Acererak the Archlich to your hand and venture into a dungeon.

Tomb of Annihilation 

Dungeon of the Mad Mage 

Interestingly, you may choose to venture into any of the three new dungeons. If you choose to venture repeatedly into Dungeon of the Mad Mage or Lost Mine of Phandelver, Acererak the Archlich will always return to your hand upon entering the battlefield. A few MTG cards synergize with Acererak the Archlich, enabling you to venture through dungeons continuously to win a game.

One card that had a sales spike due to Acererak the Archlich is Aluren.

                  

The above chart shows Aluren daily average sold price (blue line) and quantity sold (green bars) since January 1st, 2021. As a result of Acererak the Archlich getting spoiled, Aluren's sales units spiked on July 5th, with the average buyer purchasing three copies. The average price for Aluren jumped from around $60 to over $100. 

Aluren is a Reserved List card from Tempest that allows any player to play a creature with three or fewer mana at instant speed for free. Acererak the Archlich may be played and bounced back to your hand over and over again. You can loop venturing through Lost Mine of Phandelver Dark Pool to drain life from your opponents. Note that Dark Pool's room ability does not target opponents, so this combo works even if your opponents have hexproof from cards like Shalai, Voice of Plenty.  

Cavern Harpy 

Ukkima, Stalking Shadow 

Legacy players piloting the format's Aluren deck are already using Acererak the Archlich as a combo piece. Before Acererak the Archlich, players commonly used Cavern Harpy with Ukkima, Stalking Shadow or Parasitic Strix to drain life from opponents endlessly. Acererak the Archlich also benefits from being a black creature since Cavern Harpy can protect it from removal. Nevertheless, the below Aluren decklist played by otaba went 5-0 in a recent MTGO Legacy League without using Cavern Harpy, Ukkima, Stalking Shadow, or Parasitic Strix.

Magic: The Gathering TCG Deck - Aluren by otaba

'Aluren' - constructed deck list and prices for the Magic: The Gathering Trading Card Game from TCGplayer Infinite!

Created By: otaba

Event: MTGO Legacy League

Rank: 5-0

Legacy

Market Price: $4168.94

Cards

Crime // Punishment

Color Identity:B,G,W

Market Price: $12.44

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/13844_200w.jpg

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Abrupt Decay

Color Identity:B,G

Market Price: $4.80

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/128562_200w.jpg

This spell can't be countered.
Destroy target nonland permanent with mana value 3 or less.

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Aluren

Color Identity:G

Market Price: $103.63

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/5455_200w.jpg

Any player may cast creature spells with mana value 3 or less without paying their mana costs and as though they had flash.

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Veteran Explorer

Color Identity:G

Market Price: $0.24

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/218924_200w.jpg

When Veteran Explorer dies, each player may search their library for up to two basic land cards, put them onto the battlefield, then shuffle.

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Uro, Titan of Nature's Wrath

Color Identity:G,U

Market Price: $11.35

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/206836_200w.jpg

When Uro enters the battlefield, sacrifice it unless it escaped.
Whenever Uro enters the battlefield or attacks, you gain 3 life and draw a card, then you may put a land card from your hand onto the battlefield.
Escape—{G}{G}{U}{U}, Exile five other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

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Veil of Summer

Color Identity:G

Market Price: $7.54

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/192543_200w.jpg

Draw a card if an opponent has cast a blue or black spell this turn. Spells you control can't be countered this turn. You and permanents you control gain hexproof from blue and from black until end of turn. (You and they can't be the targets of blue or black spells or abilities your opponents control.)

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Phyrexian Tower

Color Identity:B

Market Price: $17.97

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/216140_200w.jpg

{T}: Add {C}.
{T}, Sacrifice a creature: Add {B}{B}.

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Snow-Covered Forest

Color Identity:G

Market Price: $0.86

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/230146_200w.jpg

({T}: Add {G}.)

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Carpet of Flowers

Color Identity:G

Market Price: $21.39

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/6809_200w.jpg

At the beginning of each of your main phases, if you haven't added mana with this ability this turn, you may add X mana of any one color, where X is the number of Islands target opponent controls.

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Brainstorm

Color Identity:U

Market Price: $0.54

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/243841_200w.jpg

Draw three cards, then put two cards from your hand on top of your library in any order.

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Fatal Push

Color Identity:B

Market Price: $1.74

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/218830_200w.jpg

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

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Force of Will

Color Identity:U

Market Price: $100.88

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/218698_200w.jpg

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

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Bayou

Color Identity:B,G

Market Price: $594.02

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/1342_200w.jpg

({T}: Add {B} or {G}.)

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Thoughtseize

Color Identity:B

Market Price: $12.96

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/218934_200w.jpg

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

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Living Wish

Color Identity:G

Market Price: $0.96

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/161427_200w.jpg

You may reveal a creature or land card you own from outside the game and put it into your hand. Exile Living Wish.

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Tropical Island

Color Identity:G,U

Market Price: $740.86

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/1595_200w.jpg

({T}: Add {G} or {U}.)

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Verdant Catacombs

Market Price: $24.45

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/238611_200w.jpg

{T}, Pay 1 life, Sacrifice Verdant Catacombs: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

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Snow-Covered Swamp

Color Identity:B

Market Price: $0.89

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/230149_200w.jpg

({T}: Add {B}.)

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Grist, the Hunger Tide

Color Identity:B,G

Market Price: $6.19

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/239619_200w.jpg

As long as Grist, the Hunger Tide isn't on the battlefield, it's a 1/1 Insect creature in addition to its other types.
+1: Create a 1/1 black and green Insect creature token, then mill a card. If an Insect card was milled this way, put a loyalty counter on Grist and repeat this process.
−2: You may sacrifice a creature. When you do, destroy target creature or planeswalker.
−5: Each opponent loses life equal to the number of creature cards in your graveyard.

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Endurance

Color Identity:G

Market Price: $33.80

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/240103_200w.jpg

Flash
Reach
When Endurance enters the battlefield, up to one target player puts all the cards from their graveyard on the bottom of their library in a random order.
Evoke—Exile a green card from your hand.

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Misty Rainforest

Market Price: $28.13

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/238609_200w.jpg

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

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Snow-Covered Island

Color Identity:U

Market Price: $1.06

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/230148_200w.jpg

({T}: Add {U}.)

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Savannah

Color Identity:G,W

Market Price: $381.92

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/1552_200w.jpg

({T}: Add {G} or {W}.)

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Plague Engineer

Color Identity:B

Market Price: $1.50

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/190985_200w.jpg

Deathtouch
As Plague Engineer enters the battlefield, choose a creature type.
Creatures of the chosen type your opponents control get -1/-1.

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Underground Sea

Color Identity:B,U

Market Price: $964.17

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/1599_200w.jpg

({T}: Add {U} or {B}.)

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Ponder

Color Identity:U

Market Price: $2.44

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/236200_200w.jpg

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

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Cabal Therapy

Color Identity:B

Market Price: $0.82

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/118439_200w.jpg

Choose a nonland card name. Target player reveals their hand and discards all cards with that name.
Flashback—Sacrifice a creature. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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Acererak the Archlich

Color Identity:B

Market Price: $9.01

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/243442_200w.jpg

When Acererak the Archlich enters the battlefield, if you haven't completed Tomb of Annihilation, return Acererak the Archlich to its owner's hand and venture into the dungeon.
Whenever Acererak the Archlich attacks, for each opponent, you create a 2/2 black Zombie creature token unless that player sacrifices a creature.

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Academy Rector

Color Identity:W

Market Price: $109.06

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/6135_200w.jpg

When Academy Rector dies, you may exile it. If you do, search your library for an enchantment card, put that card onto the battlefield, then shuffle.

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Knight of Autumn

Color Identity:G,W

Market Price: $0.51

ImageURL: https://tcgplayer-cdn.tcgplayer.com/product/243826_200w.jpg

When Knight of Autumn enters the battlefield, choose one —
• Put two +1/+1 counters on Knight of Autumn.
• Destroy target artifact or enchantment.
• You gain 4 life.

Buy This Card! https://www.tcgplayer.com/product/243826/magic-commander-adventures-in-the-forgotten-realms-knight-of-autumn

Commander players may want to run the Acererak the Archlich and Aluren combo in various decks. 

Commanders such as Thrasios, Triton Hero // Tymna the Weaver and Cazur, Ruthless Stalker/Ukkima, Stalking Shadow offer synergies with the combo. Acererak the Archlich is particularly appealing for Cazur, Ruthless Stalker/Ukkima, Stalking Shadow decks since the combination of Ukkima, Stalking Shadow, Cavern Harpy, and Aluren is already game-ending.

Rooftop Storm

Aluren is not the only card that saw a sales unit spike from the reveal of Acererak the Archlich. Rooftop Storm is a six-mana enchantment that enables you to cast Zombie creatures for free. Since Acererak the Archlich is a Zombie Wizard, you can repeatedly play it with Rooftop Storm and venture through Lost Mine of Phandelver to win a game.

Rooftop Storm had a sales unit spike on July 5th, with the average buyer purchasing two copies. Surprisingly, Rooftop Storm's average market price saw no significant upward movement after the sales spike. One reason for Rooftop Storm's lack of price shifting might be its narrow playability with Acererak the Archlich. Rooftop Storm is perhaps too slow and narrow for Constructed formats since it only works with Zombie creatures.

The Scarab God 

Gisa and Geralf 

The Acererak the Archlich and Rooftop Storm combo ideally fits in an existing Dimir or Esper Zombie Commander deck. The Scarab God and Gisa and Geralf are probably the two best blue-black commanders for running the combo since players may already have Rooftop Storm in their 99. Varina, Lich Queen is a great commander choice for Esper Zombie decks.

Mitotic Slime

Other than Zombies, there is another tribe that benefited from Forgotten Realms. 

Gelatinous Cube 

Two new Ooze creatures are found in Forgotten Realms, bringing the total Commander-legal Ooze creature count to 35. Gelatinous Cube is a black creature with a similar ability to Fiend Hunter in that it can exile a creature controlled by an opponent until Gelatinous Cube leaves play. Also, you may pay the exiled creature's mana value plus one black mana to put it into your opponent's graveyard.

Ochre Jelly is the other Ooze in Forgotten Realms. As a rare green creature, Ochre Jelly is quite potent. It enters the battlefield with X +1/+1 counters and trample. When Ochre Jelly dies, you get to create a creature token copy of it with half as many +1/+1 counters, rounded down.

The spoilers for Gelatinous Cube and Ochre Jelly resulted in another Ooze creature spiking.

Mitotic Slime saw an increase in sales leading into the Forgotten Realms spoiler season, possibly due to Chatterfang, Squirrel General. The most significant spike in price and sales occurred on June 29th, the same day Gelatinous Cube and Ochre Jelly got spoiled. Buyers purchased an average of five copies of Mitotic Slime on June 29th, driving its average sold price to $3. While $3 is a relatively small amount of money for an MTG card, it is three times higher than Mitotic Slime's average market price before the buying frenzy.

Mitotic Slime's buyout appears to be speculative since it only sees play in Commander. Anyone sitting on copies may want to sell into the hype. I foresee the average market price of Mitotic Slime dropping in price after the current demand subsides.

Necrotic Ooze

One other Ooze creature spiked due to Forgotten Realms, but not because of Gelatinous Cube or Ochre Jelly

Necrotic Ooze had two sales spikes in 2021. The first spike at the end of May was a buyout averaging over five copies per buyer. On July 7th, a second spike occurred with average unit sales of almost three copies per buyer. Near Mint copies of Necrotic Ooze jumped from around $3 to over $5.

Players bought copies of Necrotic Ooze recently because of its interaction with Asmodeus the Archfiend.

Asmodeus the Archfiend has an activated ability that costs three black mana to draw seven cards. Necrotic Ooze copies the activated abilities of all creatures in all graveyards, thus allowing you to use Asmodeus the Archfiend's draw seven cards ability if it is in a graveyard. There are many ways to put Asmodeus the Archfiend into your graveyard (Entomb, Vile Entomber, Buried Alive, etc.) in a black deck to fuel card draw with Necrotic Ooze

Among the card spikes mentioned above, I believe Aluren will most likely maintain its price increase in the near term. Aluren already saw some play as a Reserved List card in Legacy and Commander. Legacy Aluren decks may be more potent with Acererak the Archlich since the combo does not rely on Cavern Harpy to execute. I wouldn't expect much of a market price retrace for Aluren any time soon.

Aeve, Progenitor Ooze 

Biowaste Blob 

Speaking of Commander, WotC is making a noticeable effort to increase the power level of Oozes. Recent sets include a handful of new and exciting Ooze creatures. Aeve, Progenitor Ooze is a legendary Ooze with storm from Modern Horizons 2. Commander Legends gave us Biowaste Blob, which pumps all Ooze creatures +1/+1 and Slurrk, All-Ingesting, the first Ooze with partner. Shapeshifter creatures from Kaldheim, including Realmwalker and Bloodline Pretender, can support Ooze tribal as well. There's probably never been a better time for Oozes in the history of Commander.