Koth of the Hammer: Official Thread

Malcrof
Malcrof Posts: 5,971 Chairperson of the Boards
edited March 2017 in Planeswalker Details
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Cost to Max Level: 79,920 runes

manared.pngKoth

1: Reshape the Land - cost: 6
1 - destroy 3 random non-red gems
2 - destroy 6 random non-red gems
3 - destroy 9 random non-red gems
4 - destroy 12 random non-red gems

2: Rage of the Mountain - cost: 12
1 - all your creatures get +2/0, Trample & Berserker until end of your turn
2 - all your creatures get +4/0, Trample & Berserker until end of your turn
3 - all your creatures get +6/0, Trample & Berserker until end of your turn
4 - all your creatures get +8/0, Trample & Berserker until end of your turn

3: Strength of the Mountain - cost: 20
1 - create Support (10 charges): when anyone matches red, all your creatures gain +1/+1
2 - create Support (10 charges): when anyone matches red, all your creatures gain +2/+2
3 - create Support (10 charges): when anyone matches red, all your creatures gain +3/+3
4 - create Support (10 charges): when anyone matches red, all your creatures gain +4/+4

Level 60 mana bonuses: -1 manawhite.png | managreen.png | +9 manared.png | manablack.png | -1 manablue.png
Level 60 HP: 111
Level 60 max Creatures: 10 Spells: 6 Supports: 3



Post your decks and tips for Koth below!
«13

Comments

  • Malcrof
    Malcrof Posts: 5,971 Chairperson of the Boards
    Link to old Koth Deck discussion: viewtopic.php?f=37&t=43762
  • ReddMaxx
    ReddMaxx Posts: 54 Match Maker
    I don't think Level 4 Rage of the mountain happens at level 54. I am level 57 and don't have it yet.

    Redd
  • Malcrof
    Malcrof Posts: 5,971 Chairperson of the Boards
    ReddMaxx wrote:
    I don't think Level 4 Rage of the mountain happens at level 54. I am level 57 and don't have it yet.

    Redd

    They don't, Kiora's are different as well, i am working on getting more accurate info , will take that part down for now, thank you for the info!
  • Morphis
    Morphis Posts: 975 Critical Contributor
    Copy-pasted from another thread.
    "How I play koth"

    For me it goes like this:
    - match reds. Of course but more important than others.
    4 other color matches? No thanks.
    2 matches of 3 colors non red? No thanks.
    - cpu will not match your gems when can match his gem most of the time.
    So if you can choose between a bad match that will setup a red match for next turn and denying opponent color, choose the setup.
    Opponent will then match his color and you yours.

    - if none is good choose to match planeswalker symbol

    - use the first skill only if needed and if there is a decent chance(couple red near but not matchable, lots of red around) to setup a red match or get a cascade with red match.
    If you have a red match already usually it is a bad move to use first skill. It could screw the red match or not help anyways.
    Random cascades unless lead to red auto-matching, are pointless.



    I think giving my deck lists for almost any deck is pointless...
    Too many mythics, if you are already at that point you do not need a guide XD

    Discussion on deck building could be interesting though.
  • EDHdad
    EDHdad Posts: 609 Critical Contributor
    I'm very interested in Koth deckbuilding theory, and would love to see anyone's list.

    At present, my Koth is only level 12. I'm spending my runes trying to level up Sarkhan to 60 before I build up Koth.

    On the plus side, all of my opponents are also at level 12 and PvP matches often don't take more than 2 minutes to complete, netting many runes per hour (though very few ribbons).

    At present, my build looks like this. I'm concentrating on effects which destroy gems, except Volcanic Upheaval because it doesn't help against a red opponent). Also, note that at level 12 I'm maxed out on the number of spells (4) and supports (1) I can put in my deck. At a higher level, I would probably want Mirrorpool and/or Devour in Flames.:

    Demolish (destroys gems)
    Exquisite Firecraft
    Volcanic Rambler (destroys gems)
    Sword of the Animist (destroys gems)
    Rolling Thunder (mana sink and non-targeted mass damage)
    Jori-En Ruin Diver (draw)
    Scour from Existence (removal)
    Abbot of Keral Keep (destroys gems)
    Scab-Clan Berserker (creature removal or beater)
    Embermaw Hellion (pump, removal, beater)

    A couple of questions for those with more advanced Koth decks:

    * Have you had any success playing Mina and Denn Wildborn to turn gems red?

    * How fast and consistent is a level 60 Koth in PvP mode? Does the speed and/or win rate suffer much from color screw?
  • Abenjes
    Abenjes Posts: 253 Mover and Shaker
    When I first brought Koth I levelled him straight to lvl60, built a deck and promptly lost all my games. I regret not trying him out at lower levels to get a feel for him.
    Koth lives and dies by red gem matching if you can't match red gems he suffers badly, I find he struggles against any other red planeswalker that can match first.
    his first ability doesn't always generate red matches so you have to have a back up in case the dual lands help a bit, I'll try Mina and Denn tonight and see if that works.
    he also suffers from card draw and if not carefull Lianna can destroy him, Jori-En Ruin Diver is fantastic for this, Jayamaydes tome has also been suggested.
    I've found him to be quick and powerful in QB, but of all the planeswalkers he can go to **** the quickest.
  • Malcrof
    Malcrof Posts: 5,971 Chairperson of the Boards
    This is my Koth QB Deck (also worked well for the event, but swapped out animist for scour). Had a 36 fight win streak with this deck, could have been longer but freezes started. I do not have many mythics, so as my deck gets stronger, this is sure to change.

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  • Morphis
    Morphis Posts: 975 Critical Contributor
    Ok I will link my current deck(still subject to changes, Koth is the last planeswalker I got).

    ZfHhTZq.jpg

    There are differences with other deck builds.

    I used to run both gem destroyers, abbot and rumbling.
    Then remove abbot cause with no draw card looked inefficient.
    I realized soon enough that while on paper it looks a good idea to destroy gems to get red matches with cascades or setup to manually match those red, there is a problem... You actually need to charge these cards, and with no red matches in the first place, even 8 mana is a lot.

    So it was better to just "bet" on red matches being there to cast big creatures.

    Creatures... I really wanted to make it work with 4 but... You know what is worse than having no red match?
    Having red match a nothing to actually fill that plays actively.
    Yes sometimes you fill 3 spells that will help later... But it is better to play something now and charge those later.

    Creatures of choice are all great.
    Tyrant: great stats and 6 AOE damage. Sometimes I charge it and wait his first creature for a huge tempo swing.
    Skaab berserk: already found it good pre patch. With reduced mana cost is great. Helps a lot in reducing damage taken.
    Omnath: any deck with gem manipulation can get big advantage out of it. It also procs on opponent landfall.
    Firebird: 8/8 haste flyer for 15 is great. Really unlikely you will resurrect it, but when you do is fantastic.
    Embermaw: always a good creature. Only "not great" if played as first creature.

    Supports: mirrorpool. Any of these creature become a huge threat with mirrorpool.
    Smoldering marsh to help getting the red matches.

    Spells: damage spells for medium/big creatures. Creature over 6 health can be dealt with a combination of these or one + tyrant.
    Demolish to handle supports. It looks like stall supports like hixus, clausteophobia, etc are coming back. If the support is in a bad spot even at 1 shield can be painful to remove.
    Also Koth skill can easily make the support go to the bottom, where is harder to remove.

    Think my average time in QB is 3 - 3 and half minute. Usually it takes like 6 or more fight until I have to switch cause of health.
    Basically health loss depends a lot on skaab coming soon or later(or not at all) and of course luck in burst damage early.
  • Malcrof
    Malcrof Posts: 5,971 Chairperson of the Boards
    Morphis wrote:
    Ok I will link my current deck(still subject to changes, Koth is the last planeswalker I got).
    ZfHhTZq.jpg
    There are differences with other deck builds.

    I used to run both gem destroyers, abbot and rumbling.
    Then remove abbot cause with no draw card looked inefficient.
    I realized soon enough that while on paper it looks a good idea to destroy gems to get red matches with cascades or setup to manually match those red, there is a problem... You actually need to charge these cards, and with no red matches in the first place, even 8 mana is a lot.
    I like running them w/ Hangarback for the sheer number of Thopters i can get out when they enter, for now anyway.. It looks like once i get a few of those rares/mythics i may change!
  • Morphis
    Morphis Posts: 975 Critical Contributor
    Used to run hangarback but animation time kills its viability to compete in QBs.
    Omnath already covers the same niche with less procs but more value out of each one.
    Hangarback is also better if killed but then again... 8 thooters proc take too much time :/
  • madwren
    madwren Posts: 2,259 Chairperson of the Boards
    My deck's tried a lot of creature combinations, but I've settled on a standard deck that's been steamrolling. This deck has evolved. At lower levels, I used a lot of gem destruction (the twin Volcanics, Rambler and Eruption) to help stimulate mana production. However, once I got to the point I wasn't generating negative mana matches, I found it was better simply to focus on dropping synergistic bombs.

    Creatures -
    Mina and Denn, Wildborn
    Embermaw Hellion
    Scab-Clan Berzerker
    Jori En, Ruin Diver
    Iroas's Champion

    The red-green conversion of M&D is awesome, plus this is a mana-efficient 6/6 body. Additionally, being able to trigger berserker makes for excellent removal. Embermaw is of course fantastic; it makes IC nearly unbeatable in combat and boosts everyone else. My biggest problem was that I kept running out of cards, and needing card draw. Voila, enter Jori En, who keeps my hand filled.

    Spells: 2
    Scour from Existence
    Devour in Flames

    Scour fills from one red match and takes care of any troublesome blockers. Devour in Flames is a removal spell that I can cast when there aren't any red gems on the board. That alone makes up for the 5-mana gift.

    Support:
    Mirrorpool
    Smoldering Marsh
    Cinder Glade

    Marsh and Glade are cheap, and help when you get a bad board state or against Devoid. Mirrorpool is, to be honest, awesome. Whether you're dropping 10/12 Embermaws, or 12/12 hasty Scab-Clans that become 15/15 on the second or third turn, you win games fast.

    There are many other creatures that are viable. Abbot of Keral Keep was in before Jori En; I also used Flayer Drone for a bit (first strike) because it was a poor man's version of IC, and Mirrorpooling out an 8/4 first striker for 15 mana is pretty nice. Avaricious Dragon has the size and evasion I like, but in matches against Chandra/Koth he kept destroying red gems, which was a tremendous handicap. Obviously, all the creatures should be red for Embermaw goodness.

    The deck has a lot of redundancy. Gem creation in the two supports and Mina/Denn. Berserker in Embermaw, IC, and Koth's 2nd ability. Large bodied creatures backed up by Mirrorpool, unconditional removal plus cheap repeatable removal. I love it.

    Usually it wins in the 3-4 minute range. I've had some incredibly explosive starts where I have a board filled with creatures in one turn, which is pretty enjoyable.
  • Abenjes
    Abenjes Posts: 253 Mover and Shaker
    I can confirm. Mina and Denn work extremely well with Koth, the synergy speeds him up and being a 6/6 creature is not too bad.
    this seemed to be the card I was looking for as my Koth deck worked really well in this weekends events, I've still to try this latest version in QB if it does well I'll post it.
  • PapiLouis4
    PapiLouis4 Posts: 113
    Abenjes wrote:
    I can confirm. Mina and Denn work extremely well with Koth, the synergy speeds him up and being a 6/6 creature is not too bad.
    this seemed to be the card I was looking for as my Koth deck worked really well in this weekends events, I've still to try this latest version in QB if it does well I'll post it.

    im playing with a lvl 46 koth atm, and so far ive just been running through everything, excpet for one encounter against ajani where i couldnt get any matches and he kept cascading like crazy....ended up winning that battle with 1 hp lol

    anyways at the moment im running this deck

    Tyrant of Valakut (kill stuff)
    Akoum helkite (kill more stuff)
    iroas champion (kill even more stuff)
    mina and denn (gem generator and allows other to kill stuff)

    brutal expulsion (pretty much just in here to bounce undergrowth cahmpion)
    exquisite firecraft (kill stuff)
    ravaging blaze (kill stuff)
    demolish (support destruction)

    cinder glade (red gems)
    smoldering marsh (moar red gems!)

    as you can see, theres a common theme here. ive yet to lose a match, and every now and then i do end up with few cards in hand, but almost always by round 2 its already game over
  • Slytechs
    Slytechs Posts: 14
    PapiLouis4 wrote:
    Abenjes wrote:
    I can confirm. Mina and Denn work extremely well with Koth, the synergy speeds him up and being a 6/6 creature is not too bad.
    this seemed to be the card I was looking for as my Koth deck worked really well in this weekends events, I've still to try this latest version in QB if it does well I'll post it.

    im playing with a lvl 46 koth atm, and so far ive just been running through everything, excpet for one encounter against ajani where i couldnt get any matches and he kept cascading like crazy....ended up winning that battle with 1 hp lol

    anyways at the moment im running this deck

    Tyrant of Valakut (kill stuff)
    Akoum helkite (kill more stuff)
    iroas champion (kill even more stuff)
    mina and denn (gem generator and allows other to kill stuff)

    brutal expulsion (pretty much just in here to bounce undergrowth cahmpion)
    exquisite firecraft (kill stuff)
    ravaging blaze (kill stuff)
    demolish (support destruction)

    cinder glade (red gems)
    smoldering marsh (moar red gems!)

    as you can see, theres a common theme here. ive yet to lose a match, and every now and then i do end up with few cards in hand, but almost always by round 2 its already game over

    I'm running pretty much the same deck, aside the fact I am missing Tyrant, Akoum and Ravaging icon_e_sad.gif Instead, I run Mirrorpool, Rolling Thunder (insta fill with Mirrorpool, a cheaper version of Tyrant), Embermaw, Scab Clan Berserker. It is a very solid cheaper version of yours.
  • PapiLouis4
    PapiLouis4 Posts: 113
    Slytechs wrote:
    PapiLouis4 wrote:
    Abenjes wrote:
    I can confirm. Mina and Denn work extremely well with Koth, the synergy speeds him up and being a 6/6 creature is not too bad.
    this seemed to be the card I was looking for as my Koth deck worked really well in this weekends events, I've still to try this latest version in QB if it does well I'll post it.

    im playing with a lvl 46 koth atm, and so far ive just been running through everything, excpet for one encounter against ajani where i couldnt get any matches and he kept cascading like crazy....ended up winning that battle with 1 hp lol

    anyways at the moment im running this deck

    Tyrant of Valakut (kill stuff)
    Akoum helkite (kill more stuff)
    iroas champion (kill even more stuff)
    mina and denn (gem generator and allows other to kill stuff)

    brutal expulsion (pretty much just in here to bounce undergrowth cahmpion)
    exquisite firecraft (kill stuff)
    ravaging blaze (kill stuff)
    demolish (support destruction)

    cinder glade (red gems)
    smoldering marsh (moar red gems!)

    as you can see, theres a common theme here. ive yet to lose a match, and every now and then i do end up with few cards in hand, but almost always by round 2 its already game over

    I'm running pretty much the same deck, aside the fact I am missing Tyrant, Akoum and Ravaging icon_e_sad.gif Instead, I run Mirrorpool, Rolling Thunder (insta fill with Mirrorpool, a cheaper version of Tyrant), Embermaw, Scab Clan Berserker. It is a very solid cheaper version of yours.

    yeah i was running scab and embarmaw before, but i like having the option when to make them berserk not just always smash into the opponents creatures like those 2 berserkers do
  • madwren
    madwren Posts: 2,259 Chairperson of the Boards
    Rolling Thunder is pretty nice. At first, I didn't realize that if you Awaken it, it does a total of 6 damage to every creature and planeswalker--it first does the normal 2, then the 4 from awakening it. Reading the text, I thought it did 4 total when awakened. Nope.
  • PapiLouis4
    PapiLouis4 Posts: 113
    madwren wrote:
    Rolling Thunder is pretty nice. At first, I didn't realize that if you Awaken it, it does a total of 6 damage to every creature and planeswalker--it first does the normal 2, then the 4 from awakening it. Reading the text, I thought it did 4 total when awakened. Nope.

    yeah i used it for a little while then got rid of it, i almost never have 3 opponent creatures out, so i felt it wasnt very efficient for me. its also the reason why they lowered the cost of chandras ignition icon_e_wink.gif
  • Slytechs
    Slytechs Posts: 14
    PapiLouis4 wrote:
    madwren wrote:
    Rolling Thunder is pretty nice. At first, I didn't realize that if you Awaken it, it does a total of 6 damage to every creature and planeswalker--it first does the normal 2, then the 4 from awakening it. Reading the text, I thought it did 4 total when awakened. Nope.

    yeah i used it for a little while then got rid of it, i almost never have 3 opponent creatures out, so i felt it wasnt very efficient for me. its also the reason why they lowered the cost of chandras ignition icon_e_wink.gif

    yeah, those are all nice cards, if I had them, I wouldn't run Rolling, Ember or Scab Clan...if only they would make the option to have a "Black Market" type of shop to buy the missing cards to a collection. Or maybe make the shop available after you have lets say 80% of all the cards...its pointless for me to buy any packs right now, yet all I'm missing is a couple Mythics I could fancy and upgrade my current decks (Exert, Chandras ignition, Bring to Light, UC, and the likes). Oh well, dreams icon_e_sad.gif
  • HomeRn
    HomeRn Posts: 330 Mover and Shaker
    In the old Koth thread, I had mentioned that I had a Eldrazi deck that was starting to become a monster - and it was capable of taking down Kozilek in the events (albeit it was usually VERY close!). I now regret to inform you... I've made it even better... if only I could see how many people lose to this deck in QB...

    Creatures (4):

    Oblivion Sower
    Ulamog, the Ceaseless Hunger
    Void Winnower
    Kozilek, the Great Distortion

    Spells (5):

    Titan's Presence
    Crumble to Dust
    Brutal Expulsion
    Scour from Existence OR Demolish
    Serpentine Spike

    Supports (1):

    Shrine of the Forsaken Gods

    Bolded cards above have Devoid.

    This deck revolves around Koth's large burst mana gains around red matches to get the massive Eldrazi beatsticks out while filtering out the other colors to keep the board loaded with manared.png to keep the Eldrazi train moving. The deck is a bit spell heavy, especially with control spells as none of the Eldrazi have Defender or Berserker in this deck.

    Crumble to Dust is the deck's secret weapon... it's basically Koth's first ability on steroids! Ingesting every manawhite.png and manablue.png on the board can really clean up the board while having a strong chance to cascade and/or add manared.png which Koth needs desperately. Titan's Presence is stupidly powerful early on when I'm trying to get the Eldrazi beatsticks out - three of the four Eldrazi in the deck will allow Titan's Presence to be played, 2 mana to destroy nearly any huge threat is a deal. Serpentine Spike is one of the most flexible damage spells bar none; you can destroy a massive defender or clear the entire enemy board for a gigantic tempo swing. Brutal Expulsion can also be a very nasty surprise - who would expect bounce effects from Koth? Shrine of the Forsaken Gods is simply too good in an Eldrazi deck -a 5 mana investment for 3 mana every turn AND 2 mana to the first colorless card from 3 target gems? Yes, please.

    The Eldrazi in the deck are all colorless Mythic Rares... but that's the price you'll have to pay for an Eldrazi deck that's actually playable in a lot of cases, especially for Koth! Oblivion Sower is amazing for Koth - ingesting 10 of your opponent's gems and then processing 5 of them to manared.png is HUGE; a big body (6/9), modest ramp effect, AND mana disruption for only 14 mana! Ulamog is brutal if not dealt with immediately - 10/10 for 21 mana - but the fact that it constantly denies my opponent mana by ingesting EVERY gem of their color can be downright game breaking (especially against Kiora). Void Winnower can really accelerate this deck is ludicrous speeds - 3 mana from every match my opponent gets adds up very quickly, let alone the fact it allows me to deal with cards that would normally shut down decks... I'm looking at YOU Undergrowth Champion. Then there's the recently released Kozilek. Gigantic 12/12 statline, refills my hand, has Menance, who can also give mana to every card in my hand WHILE denying mana to my opponent. Once Kozilek shows up, it's practically GG if not dealt with the turn it shows up.

    This deck is currently on a 45 game win streak with only one close call against a Gideon with an absurd number of control spells (Scour, Smite the Monstrous, Swift Reckoning, etc.). Not to mention it has utterly DESTROYED every single Kiora deck so far. Hard to do Kiora's strategies when you cannot get mana for them because of the ingest effects!
  • Dodecapod
    Dodecapod Posts: 96 Match Maker
    First off, after tinkering around a bit and gaining some experience with Koth over the last few weeks, I have to say that despite how much I enjoy playing red decks (Chandra was my default QB PW previously, and Deadguy-era Sligh was an old favorite way back when in paper MtG), his power level is absurd right now (arguably even more than Chandra with her first ability at 3 loyalty); for anyone who hasn't purchased Koth yet, a nerf at some point could be virtually inevitable, so it might be better to hold off on buying him for now to see if and when he gets changed, unless runes are overflowing and he can be maxed (or close to it) immediately (in which case it's never too soon to jump on the OP bandwagon, assuming a decent selection of strong red cards to work with).

    Anyway, on to the deck itself; unsurprisingly, the core of my Koth QB deck is essentially similar to other examples posted so far (namely Mirrorpool + large creatures), and a lot of great points have been addressed already, so instead of rehashing those I'll try to focus on the differences from other lists and explain some of the deckbuilding process that led to this version. I wanted to err on the side of inclusion for those who might be less familiar with Koth and interested in a detailed example of his playstyle, but in light of some of the lengthy descriptions to follow, each section is collapsible for convenience, and much of the exposition can safely be skipped for those who already have some experience with level 60 Koth and are mostly just interested in the decklist itself.

    Xa5kug6.jpg?1

    Theory:
    The most unique feature of this deck is probably the high number of creatures despite only having 3 board slots available to make use of them; initially, it might seem like a waste to have to exile or replace creatures multiple times over the course of a game, but there are a few factors that eventually proved to be more important while testing various Koth decks:
      1.
    Mirrorpool - With other versions, Mirrorpool ironically tended to decrease the win rate despite how powerful the card can be, and it took a while to realize that the reason for this was winding up in too many situations with multiple fully charged spells and/or supports in hand, but no threats and too few answers. While other PWs (e.g. Kiora, Sarkhan, Ob Nixilis, etc.) can often address this issue with card draw and filtering, red's options for card advantage are limited, so the better solution seemed to be adding more creatures instead, in order to minimize the frequency of having dead Mirrorpools in hand.
      2.
    Koth's 2nd and 3rd abilities - Both of these are weak with 1 creature on the board, good with 2, and strong with 3; while tokens (e.g. from Omnath, Hangarback Walker, or Akoum Stonewaker) are another way to fill as many slots as possible as often as possible, they don't synergize as well with Mirrorpool, so increasing the creature card count seemed like a more reliable way to accomplish the same goal. (To be fair, I don't have either of the mythic token generators mentioned, but I wouldn't be likely to add them even if they were to drop tomorrow, because of how crucial Mirrorpool is to maximizing the speed of this deck.)
      3.
    Number of cards used in a typical game - This probably should have been the most obvious element from general experience with MtGPQ, but it wasn't until trying to figure out why Mirrorpool wasn't working that I thought enough about it to realize what was happening. In most games, the worst 1-3 cards in hand at any given time would never be played, so it didn't matter whether they were creatures 4-6, situational spells, or backup supports. On the other hand, extra creatures would increase the odds of having active threats available in the opening hand and recovering quickly from board wipes, and would address points 1 and 2 in the process. This was what finally convinced me that playing with 6+ creatures could potentially be viable in a consistent QB deck, as I was reluctant to seriously consider the idea at first.
    Card Choices:
    Most of these are just the usual suspects (Embermaw, Scab-Clan Berserker, Jori En, etc.), but there are a few cards worth mentioning specifically:
      Reckless Bushwhacker - This is probably the most unusual card in the deck; while Akoum Stonewaker, Chasm Guide, Lavastep Raider, and Valakut Invoker aren't necessarily bad alternatives for this slot among the lower rarities (most rarer creatures are too expensive to be comparable), the combination of haste and increasing efficiency with multiple creatures (especially if they're played on the same turn) makes Bushwhacker ideally suited for this deck.
        Akoum Hellkite - This is probably the MVP next to Mirrorpool; it can be dropped in 1 turn off of any red match, flies over the dreaded Undergrowth Champion in many cases, and sometimes complements the relatively sparse removal when enemy flyers or other annoying creatures start to become a problem.
          Abbot of Keral Keep - It's still playable even without the card draw, but would be the first creature I'd replace if something better came along. Most of the time, Volcanic Rambler is more efficient now, even if Abbot is occasionally more resilient against removal or defenders.
            Ravaging Blaze - There's probably a viable case for favoring Devour in Flames in this slot instead, or potentially Brutal Expulsion for the sole purpose of removing Undergrowth Champion. Other spells (e.g. Scour from Existence, Turn Against, Rolling Thunder, and maybe a few more) seem like a step down, since they're a bit too reactive in a deck that aims to win by turn 4-6 if all goes according to plan.
              Notable Omissions - Mina and Denn, Goblin Dark-Dwellers, and Shrine of the Forsaken Gods proved to be a bit lackluster or slow for this version after some testing; they're not bad cards in the abstract, but they usually don't gain full value until a few turns into the game, and by that time Koth will often be on the verge of winning already. The same principle applies to other mana generators and supports like Oath of Chandra.

              Leaving out Demolish might seem risky, and can admittedly lead to awkward situations every once in a while (one game in particular was very difficult to win when Hixus stacked 3 times in the bottom corner by turn 2 or 3 and remained lodged there the entire game), but on balance, only a handful of opponents use supports that are worth destroying, and even fewer will wind up playing those supports early enough to matter, so it seems more valuable to have all 10 cards in the deck dedicated to situations that arise in almost every game (this is the same rationale behind omitting specific answers to stacked Undergrowth Champions with Mantle of Webs, which red generally handles poorly).

              Put another way, there are a variety of great sideboard options or tier 1.5 cards that didn't quite seem versatile or proactive enough to make the cut for the main deck, but which might turn out to be more useful as the meta continues to evolve and new cards and PWs are released in the future.
                Potential Improvements - With access to all cards, Akoum Firebird and Tyrant of Valakut would be the first ones I'd look to add to the deck; Omnath, Locus of Rage, Desolation Twin, and Zendikar Incarnate might also be worth considering, but I'm not sure they'd turn out to be better than anything in the current list. Avaricious Dragon seems like a trap, since it's a liability against other red PWs, which are generally among the most difficult matchups anyway.
                  Budget Alternatives - Among the lower rarities, Breaker of Armies, Iroas's Champion, Akoum Stonewaker, and Devour in Flames would be among the first cards I'd consider to fill in for any missing rares or Mirrorpool. Without Mirrorpool, the creature count could be dropped safely to 4-6 in order to add in more removal or mana fixers, as the deck would lose some of its early explosiveness and could utilize middle game cards more effectively.
                  How to Play:
                  In an ideal world, Akoum Hellkite, Embermaw Hellion, and Scab-Clan Berserker are usually the 3 best creatures to have on the board (in that order), all else being equal, so these are the creatures to prioritize first if there are empty slots or if another creature needs to be replaced. Generally, the basic game plan is relatively straightforward (drop Mirrorpool, stack a creature, give it haste if needed with Bushwhacker, then ride removal and Koth's 2nd ability to victory), but there are some nuances that might not be obvious when first starting out with the deck:
                    Don't be afraid to rotate creatures - Most of the time, Volcanic Rambler or Abbot will be the best creatures to drop first, as they have the potential to cascade into the ones after them; by the time all 3 slots are filled, it's usually time to replace one or both with better options, especially if Bushwhacker will be able to give other creatures haste in the process. Likewise, once Bushwhacker has been used, it can often be replaced by Scab-Clan Berserker (sometimes even on the same turn), and drawing Mirrorpool is often enough to justify replacing any unstacked creature on the board (with the arguable exception of Embermaw) with any other creature in hand if the game is likely to last at least 2 more turns.
                      When something goes wrong, don't panic - Most of the (non-bugged) games I've lost with this deck were winnable, but barely so, and by the time I realized what I could have done, the opportunity had passed and the loss was inevitable. It might seem a little strange to have to play patiently with a hyperaggressive deck, but usually even in a desperate game there will be some window to use a combination of burn spells, Koth's 2nd ability, and any 1-2 other creatures with Bushwhacker to push through just enough damage to win. There are lots of little tricks that become apparent after playing the deck for a while, but one of the most crucial and easiest to miss is keeping track of exactly how many red gems are on the board at all times underneath animations and popups, so as to time Ravaging Blaze correctly in tough situations.
                        Balancing PW mana and Koth's abilities - Usually, if the first ability is charged, it's worth using as often as possible until all 3 creature slots are filled and 1-3 cards in hand are charged, since it helps to replace red gems over the course of the game even if it doesn't generate any instant matches. The 2nd ability tends to be relevant once or twice per game; it's almost never worth activating without at least 2 creatures on the board, and often better to save for a turn or two even once all 3 slots are filled, to leave more options for when the opponent eventually drops a creature. The 3rd ability is rarely useful with this deck; using the 2nd is generally more efficient even with 20+ PW mana available, unless the opponent has a large first-striker in play or 2+ red matches are likely to occur by next turn.
                        Results:
                        Naturally, all the theory in the world means nothing if the deck can't actually function well in practice. To that end, here are some of the highlights ever since I began keeping closer track of its performance (once I started to realize that overall it was leaps and bounds beyond any other QB deck I've ever tried up to this point, including 3-loyalty Chandra):

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                        W-L - 614-6 (~99% win rate; I've been fortunate enough not to run into any serious bugs during this span, so the depicted records are an accurate reflection, i.e. 3131-143 to 3745-149 while using this deck exclusively and tracking its progress)
                        Speed - 3-4 minutes per win (including 120 points in 61 minutes at one point; 80-100 per hour is more typical)
                        Longest winning streak - 297
                        Longest losing streak - 2
                        Fastest win (turn) - Turn 4 (multiple occasions)
                        Fastest win (time) - ~2 minutes (multiple occasions)

                        Potion Efficiency - I have yet to encounter an instance where I've had to switch PWs, even when playing continuously for 2-3 hours at maximum (or nearly maximum) speed. Most of the time fatigue is the limiting factor more than potions, as there are constant minor calculations that start to take a mental toll and lead to mistakes during longer play sessions. I haven't tracked the average use rate carefully, but would tentatively estimate one potion every 30-45 minutes as a typical benchmark after learning to play the deck optimally (others might be faster at this, but it took me a while to get a feel for how to handle tricky situations, so initially the deck required more frequent potion use to continue playing).

                        Anyway, thanks to all who have posted their decks and thoughts so far (lots of great insights in this thread for all kinds of different approaches), and good luck to everyone still working on their Koth decks (or any other PWs for that matter).