Modern Horizons becomes legal today in the paper world, but it's been tearing up Magic Online for a good week. Wizards has published two events since then: a Modern Challenge and a league. Today, we'll scour each for the hottest tech stirring up the format.

Scourge of the Format?

In the very first Horizons-featuring event published online, Hogaak, Arisen Necropolis bulldozed a Modern Challenge, and with it the tolerance of many players. I agree the deck seems quite powerful, but am always hesitant to call for bans so early into a deck's creation; after all, look what happened with Neoform. Here's the deck in all its glory:

Bridgevine received two superb sacrifice outlets in Modern Horizons: Carrion Feeder and Altar of Dementia. Together with Stitcher's Supplier and Bridge from Below, these cards help generate boards of creatures faster than opponents can even deploy their Rest in Peace. Hogaak, Bridge, and Altar together have particularly potent synergy. And that's the main draw to this strategy: its pieces work together extremely well.

What follows are the decks from the other online event published by Wizards so far. This league features plenty of Horizons-fueled innovation, which I've aimed to capture exhaustively.

Combo Summer

We led off the last brew report with a section on combo decks, and today's is no different. Horizons seems to have infused existing combo decks with some critical tech.

Once named for Collected Company, Abzan Vizier runs the same packages, but 0 copies of its "namesake" insant. Instead, this deck packs two newcomers to Modern in its spell slots: Finale of Devastation, a standout searcher from War of the Spark, and Eladamri's Call, a Commander-staple-turned-Modern-staple via timely reprint. All that searching, and at such an economical rate, helps Vizier assemble its combo with surgical precision, all while enabling a toolbox package rounded out by Yawgmoth, Thran Physician. The Human plays double-duty here as removal and card advantage should opponents find a way to weather or blank the combo.

Another creature combo deck, Kiki-Chord also forsakes Collected Company, instead running Chord of Calling and Eldritch Evolution in its spell slots. This deck boasts the ability to straight-up win if it untaps with Prime Speaker Vannifar, and gains an unlikely ally in Ice-Fang Coatl. Beating down the Kiki deck while disrupting their combo becomes a lot more difficult with Coatl in the mix, and the cantripping snake can be sacrificed to Evolution to tutor Vannifar or a bullet at no card disadvantage.

Moving on from creature combo and into artifact combo, Urza, Lord High Artificer is at his best in this Thopter-Sword shell, where he serves as combo finder (with his stall-breaking draw ability), combo enabler (by generating mana), and combo piece (by going infinite as a third cog in the Thopter-Sword engine). Mirrodin Besieged also makes an appearance here as an alternate win condition. Damping Sphere and Ensnaring Bridge also feature as findable win-buttons against certain Modern's decks.

Ain't Nuttin But a "Tribal" Thang

While Horizons may have been packed with Slivers, it's other tribes that have received more from the expansion, at least at first blush.

One of two Goblins decks featured in the latest dump, this one makes the most of Goblin Matron. The infamous Goblin drops a turn after Warren Instigator on the curve, letting it search up whichever Goblin is best-suited to make an appearance; Matron also finds removal in the form of Munitions Expert or the cheaper Tarfire. A full set of Fiery Islets sneak their way into this list as a means of mitigating mid-game flood.

Merfolk has always run a small number of noncreature spells to interact with opponents. Removal like Vapor Snag and Dismember is the most common, but Spell Pierce has also seen play in this spot. Force of Negation, though, seems like their most attractive option yet—now, the deck can continue to deploy threats while fading removal, planeswalkers, sweepers, and combos.

After some testing, David concluded this week that Unsettled Mariner probably wasn't going to make a huge splash in Humans after all, as the deck is simply too tight to accommodate it in an open metagame. But he hadn't accounted for the deck undergoing a total redesign. Granted, I don't think the stock Humans deck is going anywhere, but this new build is still intriguing—it's got seven Canopy lands to combat flooding, and those lands end up informing the shell by letting more non-Humans enter the fray. Notable additions include Giver of Runes, a one-mana Spellskite; Spell Queller, a combo-breaker from the board; and Deputy of Detention, an answer to any permanent.

Dashing Through the Snow

Horizon's snow theme has also made waves in Modern, if mostly on the back of Lore-Scale Coatl.

Here's our Collected Company deck, but this one's all value. Coatl helps deal with enemy attackers while plussing in the meantime. That the Snake succeeds here bodes well for its applications across multiple archetypes; indeed, it's even reared its head alongside Wilderness Reclamation.

No Shardless Agent here, but Coatl does a mean Baleful Strix impersonation in this port of the Legacy rock deck. It even rewards running Arcum's Astrolabe, which provides the artifact type for Tarmogoyf.

Who needs Delver of Secrets? In another Legacy port, SPIRALPRINCE chooses to omit the archetype lynchpin in favor of, you guessed it, Ice-Fang Coatl. Curiously, Delver of Secrets itself has had a strong showing since Horizons became legal, putting multiple decklists into this 5-0 dump and showing up in the Top 36 of the Modern Challenge.

Other Developments

A few more decks that caught my eye proved harder to sort under one umbrella, but here they are.

I'd heard Waterlogged Grove pegged as a breakout Horizons card for Infect, but no copies appear here. Instead, DDMEELOW stretches his manabase to support Teferi, Time Raveler, a brilliant tech that forces opponents to interact with Infect's creatures at inopportune times. It's also nuts with Inkmoth Nexus, especially considering the sheer bulk provided by Scale Up.

In a bizarre development, Soul Sisters improves post-Horizons thanks to Force of Virtue. The enchantment drastically increases the deck's potential clock without costing pilots tempo, an aspect it may have been missing to compete. It doesn't hurt that the sideboard is full of the format's best hosers.

Traverse Shadow decks once splashed white to employ Ranger of Eos as a plan to dig up more copies of Death's Shadow. Here, Ranger-Captain of Eos leaves behind a better body, but only searches one Shadow. In return, it costs just three mana, which lets players reanimate the creature with Unearth for insane value.

The Setting Sun

There are plenty of juicy lists here, and I'd love to discuss any of them further in the comments. Which piqued your interest? Do you like the direction Modern is headed post-Horizons? Drop us a line!