I built a version of Combo Slivers back in 2014. Since then Modern Horizons really juiced up the Slivers we have access to.
How does it work?
You need a mana Sliver to accelerate out The First Sliver. The full eight of them are in the deck because of how integral they are to the combo. Also, opponents tend to rudely cast removal spells on the first copy of Gemhide/Manaweft making extra copies rather important. You’re able to dump your hand quickly with one of these on the battlefield. They also help you pay for Summoner’s Pact, which is tough to do with just lands, since you’re playing full sets of Sliver Hive, Unclaimed Territory, and Cavern of Souls.
You need a Sliver that gives the rest of your team haste so you can tap them for mana immediately. Cloudshredder is best since it gives evasion as well. Firewake is necessary as a Summoner’s Pact target. The sacrifice ability of Firewake can be useful if you have a Dormant Sliver on the battlefield, which we’ll get to later.
The new Modern Horizons Sliver legend really helps the deck tick. A five-mana 7/7 is pretty large when it can come down on Turn 3. It cascades so you generate value automatically. It’s a shame that the cascade chain for Slivers doesn’t continue until after The First Sliver is on the battlefield. That’s fine, though; you just need any other Sliver in hand to continue going off.
Virulent Sliver and Summoner’s Pact are where the deck starts to look like something special and worth exploring.
With a mana Sliver and a haste Sliver out as well, those one-drops are net-neutral on mana. Eventually you’ll have all four Virulent Slivers on the battlefield. If you got in two poison earlier, it takes two unblocked attackers from there; if not, it’ll take three.
If you can’t win on the spot or fear opposing removal to break up the combo, you can always just decline to cast a Summoner’s Pact that you cascaded into. You’ll probably have to pay 2GG for one Pact next upkeep, but that’s not so bad. Better than losing.
The deck also has an aggro draw that can win Turn 3:
Turn 1: Virulent Sliver
Turn 2: Cloudshredder Sliver, attack for two poison
Turn 3: Summoner’s Pact for another Virulent Sliver (or have a second naturally). Also cast any other Sliver, attack for eight poison.
That’s about as fast as you can reasonably expect from Simic Infect. Not bad for the deck’s Plan B.
Let’s take a look at my current working list:
Creatures (33)
- 1 Firewake Sliver
- 4 Gemhide Sliver
- 1 Harmonic Sliver
- 4 Sidewinder Sliver
- 1 Darkheart Sliver
- 4 Virulent Sliver
- 1 Striking Sliver
- 2 Predatory Sliver
- 4 Manaweft Sliver
- 4 The First Sliver
- 4 Cloudshredder Sliver
- 3 Unsettled Mariner
Lands (20)
Spells (7)
Every land in the deck produces mana for Cloudshredder Sliver, which ensures you don’t stumble when you have the aggressive draw with multiple Virulent Slivers.
Predatory Sliver and Unsettled Mariner are both here to protect your creatures. Normally Predatory Sliver is used to beat your opponent down faster, but here its main purpose is to deter Plague Engineer and Lava Dart. A deck full of one-toughness creatures comes with certain risks.
Unsettled Mariner is better against cards like Fatal Push and Path to Exile as well as things that target you like Thoughtseize or Inquisition of Kozilek. It’s particularly good against cards with multiple targets, like Searing Blaze, Kolaghan’s Command, and Grapeshot.
You do need a few more one-drops to enable your best draws involving a Turn 2 Manaweft Sliver into a Turn 3 The First Sliver. The one-drops could be anything, but I’m choosing Sidewinder Sliver and Striking Sliver because the mana pairs with the manabase that needs to support Cloudshredder Sliver as best as possible.
The first copies of Darkheart Sliver and Harmonic Sliver are important as Summoner’s Pact targets. It’s really tough for Burn, Mono-Red Prowess, or really any creature-based deck to race a Darkheart Sliver. Harmonic Sliver is here mostly against Ensnaring Bridge, yet has utility against all sorts of artifacts and enchantments running around in Modern.
The only Modern-legal card featuring the exclamation mark. To Arms! generates mana if you have three or more Slivers on the battlefield and at least one is a Manaweft or Gemhide Sliver. It’s difficult to combo off on Turn 3 without a copy and the cost of running a couple To Arms! is low since it cycles cheaply enough. I’ve tested all numbers between one and four and currently like two.
Other Considerations
Leyline of Abundance is showing up in some Freed from the Real decks as a way to turbo-charge your mana creatures that you were already playing. It also serves as a win condition if you can generate infinite mana. Slivers can’t generate infinite, although it can generate a lot. I think the deck is just a touch short on mana creatures to use it consistently. It’s also pretty poor to cascade into with The First Sliver.
Intruder Alarm is a lot like To Arms! It can be hard to cast, as this manabase can’t make blue mana. That’s not such a big deal, since intruder Alarm really wouldn’t do anything without a Gemhide Sliver or Manaweft Sliver on the battlefield anyway. It’d be much more appealing with something like Sliver Queen to make infinite creatures. Too bad she isn’t Modern-legal.
Most Sliver decks play Aether Vial and Collected Company. I’ve found that I want a higher density of actual creatures and Aether Vial doesn’t help with that. Vial doesn’t help cast a Turn 3 The First Sliver.
Collected Company could be good, but you need mana to cast it. Currently there are six lands that produce green, which is below the threshold for what I’d want to consistently cast Collected Company. Of course, it’s castable once you have a mana Sliver out, and even better with Cloudshredder Sliver, but most cards are better once those are assembled.
Alternate Sliver Brew
Creatures (35)
- 4 Basal Sliver
- 4 Mindlash Sliver
- 4 Screeching Sliver
- 4 Sedge Sliver
- 1 Sliver Legion
- 2 Striking Sliver
- 1 Sliver Hivelord
- 4 Leeching Sliver
- 3 Morophon, the Boundless
- 4 The First Sliver
- 4 Dregscape Sliver
Lands (21)
Spells (4)
Dregscape Sliver can unearth any Sliver in your graveyard for just two mana. The First Sliver and Morophon, the Boundless both have hefty casting costs that would love to be reduced. Faithless Looting and Mindlash Sliver let you discard your big targets if you draw them. Screeching Sliver can mill them over if you’re lucky.
Basal Sliver can generate a ton of black mana by sacrificing most or all of your creatures. Along with Dregscape Sliver, you can unearth your entire graveyard, although you can’t attack with them all. You’d want some enters-the-battlefield abilities like from Dormant Sliver or Lavabelly Sliver. It’s still a work in progress discovering which mix is best. Still, you can hardcast a Morophon, the Boundless pretty quickly with a pile of black mana. Is there something better to cast with a bunch of black mana?
The First Sliver isn’t far off on raw power when compared to Bloodbraid Elf. People played Enlisted Wurm in their Pro Tour decks in Honolulu 2009. I believe that The First Sliver is quite strong “on its own.” Obviously you need some sort of Sliver tribal shell to support it. The deck probably wants some better hits from The First Sliver’s natural cascade, perhaps a four-drop like Dormant Sliver or Collected Company.
Combo Slivers has been surprisingly competitive for a deck full of 1/1 creatures. When those 1/1s help crank out a huge monster, it’s worth it.
The similarities are staggering.