KCI Matchup & Sideboard Guide


The RPTQ in Toronto was pretty good for me. Qualifying was nice, mainly because it lets me avoid having to play the harder, for me anyways, Modern Pre PTQs as I just can’t win those.

This Modern Pre PTQ season, I actually played the same deck for the whole season. That’s a first for me. The more I played the deck, the better I kept getting, and I started off the season by finishing 4th at a 143 man tournament. My overall win percentage with KCI was around 72%, I was 31 wins and 12 losses, I didn’t count the draws but I had 5 intentional draws. 0 unintentional draws, as I honestly don’t know how anyone can go to time with this deck, I would finish and have about 20 to 40 minutes afterwards to relax.

My KCI list has adapted and changed, and is slightly different from others. I’m not going to go into too much about game play with the deck, as you can kind of figure that out as you goldfish it. I’m going to explain my choices and help with some sideboarding and specific situations.

My list is different from others, I play a Sai in the main and I play Aetherflux Reservoir over Pyrite Spellbomb. I also play 1 Tormod’s Crypt main.

Aetherflux is primarily because I’m used to playing with it online. Time is a huge factor online due to all the clicking. In real life, it’s because I’m used to it from online, and also that I can win through Surgical on Scrap Trawler, and that it requires a lot less mental energy to kill an opponent. There are more advantages to playing Pyrite against decks like Humans, and Infect, but there are situations where I’ve won with Aetherflux that I wouldn’t have with Pyrite and the other way around as well.

Sai is nuts. I was running 2 in the main at one point, but it becomes clunky and disrupts comboing off slightly, which isn’t what you want to be doing game 1. I play 1 main because it is extremely good against decks like Humans, Hollow One, Vengevine, and any creature based deck, as they just can’t interact effectively with the card. Untapping with it just ends the game. Sai does help you while comboing off, as it can be a card engine and a massive mana advantage, however, it’s when drawing multiples while going off that lowers your chances of winning.

Tormod’s Crypt is a concession to Storm, Vengevine, KCI and random lists like Goryo’s Vengeance. It being a 0 drop artifact is also a means of accelerating the deck, as it enables Mox Opals. I have 2 more Tormod’s Crypts in the sideboard purely to help the Storm, KCI and Vengevine matchups. It helps against Dredge as well, but you’re already a huge favourite in that matchup anyways.

I win the majority of game 1s. If I’m on the play, I move from being moderately favoured to heavily favoured. There aren’t a lot of decks that can beat KCI while KCI is on the play game 1.

Against most decks game 1, I just go for it if I have it, as there are very few decks that can interact with the combo game 1. Games 2 and 3 are fun little dances that involve guessing what interaction they have and going from there. The majority of the time, if they have no clock and are passing with mana open, then I’m just happy to play lands and cantrips and pass.


I’m going to go through the 16 lists that are listed from MTG Goldfish that popped up when I clicked on their Modern section. For the most part, I agree with this list representing Modern currently. Anything that was listed is probably a positive matchup for KCI anyways.

Almost byes:
Hardened Scales Affinity

Affinity and Hardened Scales

These decks just get bent over by KCI. I would say that these are probably easier than Tron. Post board you have 4 Nature’s Claims and potentially Bolts/Sai to bring in. Game 1, you have a far faster clock, interaction and they have 0 disruption. Engineered Explosives as a mana ramp for 0 to enable Mox Opal is sometimes the right play to be able to kill their Opals, Memnites, Ornithopters, or even more stuff from the Hardened Scales side.

I side out 1 Tormod’s Crypt, 2 Chromatic Sphere, 1 Myr Retriever, 1 Mind Stone, and bring in 1 Sai, 4 Nature’s Claim. I sometimes just bring in the 4 Nature’s Claim and leave in Mind Stone, it just depends on how you feel. If you think that they have Gaddock Teeg then bring in the Bolts instead of the Nature’s Claims.


If you’re on the play, KCI is extremely favored. The only time I’ve ever lost this matchup is being on the draw and I don’t get Mind Stone or enough mana for early KCI, they get turn 3 Karn into another Karn or exile effect, into another exile effect that’s a clock, such as Ulamog. Ulamog is really the only card that matters in this matchup, the rest of the deck is pretty much air. I bring in 3 Nature’s Claim and 1 Negate. I take out Tormod’s Crypt, 2 Engineered Explosives, 1 Sai. I sometimes take out a Chromatic Sphere instead of 1 of the Explosives. With KCI, you really want to maintain a certain amount of 0 drop artifacts to help cycle for mana.


This matchup isn’t as heavily favored as Tron or the Affinity variants but it’s still favored. Game 1 is just to combo as quickly as possible. They have disruption in Thoughtseize, but that’s really about it. Their clock is slow, and they have minimal disruption. Games 2 and 3 is weird. If they have multiple Leyline of the Voids, then it’s a lot harder, if it’s Surgical Extraction then it’s a lot easier. A lot of them are playing Surgical over Leyline, so I tend to go with that, others play the Spellbomb and go with that as well. Spellbomb doesn’t really do much against KCI, it is annoying, but you can setup around it, as they have a slow clock. I’m trying out Antiquities War as a new card, but I used to have 2 Wurmcoil Engines. I try to sideboard minimally, until I feel what sideboard hate they have. If they are aggressively mulliganing then they probably have Leyline, so plan around that. I take out Tormod’s Crypt, 1 Retriever, and 1 Sphere, for 1 Wurmcoil, 1 Antiquities War, and 1 Sai. If they have Leyline then bring in Nature’s Claims, and take out another Sphere and a Mind Stone.

Grixis Shadow
Mardu Pyromancer
Jeskai Control


I feel this matchup is favoured, but many have told me otherwise. A lot of it comes from experience of play. If you can land an Engineered Explosives on 2 then the game is generally over. Game 1, I’ve won off of Sai a number of times. He’s incredibly powerful in this matchup. In on match, I had multiple Meddling Mages against me naming KCI, Engineered Explosives and Pyrite Spellbomb, and my opponent also had Mantis Rider and other large creatures. I played Sai with Trawler in play and managed to get in excess of 6-7 thopters every turn to chump/trade until I got to the point where I was attacking and then finished the game. After board, Sai is even stronger due to them removing Reflector Mages.

I normally sideboard 3 Lightning Bolt, 1 Sai, for 1 Tormod’s Crypt, 2 Sphere, and 1 Mind Stone.


Burn is weird. Game 1, the only card that matters is Eidolon of the Great Revels. Nothing else matters. It’s hard to win if they hit Eidolon, but not impossible, as I’ve killed it with Explosives and won before. If they don’t hit it then they just lose. Post board, bring in 4 Nature’s Claim, out 1 Tormod’s Crypt, 2 Sphere, 1 Sai. I’ve Nature’s Claimed my own stuff multiple times before just to gain the life and survive. I don’t believe that Lightning Bolt should come in, but it’s not something that I would be opposed to either.

Grixis Shadow

This is very slight favoured, and it’s a lot more about the player than the deck itself. If it was me with Death’s Shadow against me with KCI, then I can feel that I would probably be losing with KCI more than winning. If it’s me with KCI vs PPTQ caliber players with Death’s Shadow, then I view myself as favoured. I view that as Death’s Shadow having a lot of lines, and being complicated. The player must know the ins and outs of KCI, as well as their own deck. I do a lot of baiting and planning several turns ahead with this matchup.

In this matchup, Death’s Shadow is a bad card. KCI has 4 Grove of the Burnwillows, and can just force them to gain life and kill off the Death’s Shadow. They have to heavily lean on zombie fish for their finisher, sometimes, this just isn’t enough. Sai is a very powerful card here. Except through Temur Battlerage, none of their creatures have a means of pushing through chump blockers, so Sai can buy a ton of time. They also put themselves really low, and post board, they tend to side out the Death’s Shadows. This allows you to punish them and steal wins even if they have lots of disruption for the combo. Take out 1 Sphere, 1 Mind Stone, and 1 Engineered Explosives, bring in 1 Sai, 1 Antiquities War, 1 Wurmcoil Engine, and Dispel. If you find out that they side into Leyline, then bring in Nature’s Claim.

Mardu Pyromancer

This is a weird matchup. Game 1s KCI normally wins easily. Games 2 and 3 comes down to if they hit their Leylines and KCI doesn’t hit the Nature’s Claims. Nature’s Claims are far weaker here as the only target is Leyline. Bring in 4 Nature’s Claim, 1 Sai, 1 Antiquities War, out 1 Retriever, 1 Explosives, 2 Sphere, 1 Mind Stone, and 1 Terrarrion.

Jeskai Control

This is pretty easy, it comes down to if they hit their sideboard cards or not. They have a lot more dead cards than UW, such as Bolt, Electrolyze, and they have a much slower clock. It’s weird to sideboard against them, as some play Stony Silence and some don’t. They can tend to have other targets beside Stony Silence or Rest in Peace, so bringing in a few Nature’s Claims isn’t always wrong. I would bring in 2 Nature’s Claims, 2 Dispel, 1 Negate, 1 Antiquities War and 1 Sai. Out Tormod’s Crypt, 2 Explosives, 2 Sphere, 1 Mind Stone, 1 Retriever. If you find out that they have more Stony Silences then bring the full 4 Nature’s Claims in.

Against Jeskai, I tend to try and combo early, but if that isn’t an option, or that they are clearly demonstrating that they have counters, I will try to milk value off of Scrap Trawler, or bait different cards to pull out their counter magic, as it is substantially less counter magic than UW. They have Logic Knot and Cryptic Command. Cryptic Command is a lot easier to play around than other counter magic, but it is backbreaking when it lands. It’s critical to try and setup a key turn to happen before they can untap with 4 mana.

Bridgevine(without main deck Leyline)
Hollow One

Storm is hard, but winnable. A lot of it comes down to play/draw. My list is good against Storm, as Tormod’s Crypt buys a lot of time. It’s still not easy, and I would say that they can be favoured as well, since it’s two ships sailing in the night, but that they have disruption. I side out 2 Sphere, 2 Engineered Explosives, Sai, and side in 2 Dispel, 1 Negate, 2 Tormod’s Crypt. I haven’t ever sided in Lightning Bolts, but I could see 1 or 2 coming in instead of a Myr Retriever, but you don’t want to over sideboard too much, as you really need to maintain consistency against it.


It’s the mirror. I have an edge due to the Tormod’s Crypt, and it might buy a necessary turn.


This is very even, but if they have Leylines main, then it becomes a lot harder. You need to side into 4 Nature’s Claims for their Leylines, but it’s a hard situation due to it being their only target for the Claims. You also really want Sai, this matchup requires a lot of sideboarding, which is frustrating, as it increases your odds of fizzling while comboing off. 4 Nature’s Claims, 2 Tormod’s Crypt and 1 Sai. Take out 2 Sphere, 1 Myr Retriever, 1 Engineered Explosives, 1 Terrarrion, 2 Mind Stone.

Hollow One

I felt initially that this deck was a very unfavoured matchup, but after playing a lot more, it seems to be about even. If they’re on the play and have an early Hollow One, then it’s rough, but otherwise it’s not too bad. If KCI is on the play, then I would say that KCI is favoured, as they’re just faster. Post board, unlike against Bridgevine, Nature’s Claim is good against their deck, as you can hit Hollow Ones as well as Leylines. Bring in 1 Sai, 4 Nature’s Claim, and 1 Wurmcoil Engine. Out 1 Engineered Explosives, 2 Sphere, 1 Myr Retriever, 1 Mind Stone, 1 Terrarrion.

Unfavoured matchups
Bridgevine with Leyline main
UW Control

Infect is just simply faster and has disruption, much harder than even Storm. It can be beat, but it requires being on the play and them having a slow hand. I’m not certain if Sai is good here. I think it isn’t as it’s probably too slow, and can’t create blockers for Blighted Agent, but otherwise it would be very helpful against the rest of their creatures. Bring in 3 Lightning Bolts, 2 Dispel, 1 Negate. Out Tormod’s Crypt, 2 Sphere, 1 Myr Retriever, 1 Terrarrion, 1 Mind Stone.

Overall, I find this deck to be very good. I think the deck should probably be banned. I feel that Ancient Stirrings should be banned. I keep playing against people that just don’t understand the deck, and how it’s supposed to interact. This deck doesn’t lose to disruption by itself. It needs to be disruption along with a fast clock, as eventually the deck will find redundant pieces and combo off.

The only sideboard cards that are intimidating are Leyline of the Void, and Stony Silence. Everything else is whatever.

Damping Sphere doesn’t really do anything. Humans keeps playing this against me and it’s just annoying, but not fatal. It also doesn’t help them that half of their deck is 2 drops, and that an Engineered Explosives on two just shuts down half their board.

Stony Silence shuts down nearly all of the deck, but Sai can help in recovery. I feel that Stony Silence is the only card that is truly backbreaking, but thankfully can be hit by Nature’s Claim.

Leyline of the Void is almost nearly as bad as Stony Silence. It shuts down all of the deck’s draw Engine, and recursion, but can be hit by Engineered Explosives, and also by Nature’s Claim.

I glanced over some other guide that was posted and he suggested taking out all the Mind Stones. That’s just wrong. I’m even hesitant on taking out 1, but you have to take out something. You need 2 drop artifacts, you just need them. Otherwise, you’re not drawing enough cards, and allowing yourself to cycle through your deck more effectively.

This deck has a very high ceiling, and it rewards good play the most. I also feel that it lost a lot of its power due to people understanding the deck and how to interact with it.

Thank you, hopefully this was helpful.