Combo · ENGINE

Blade of the Ruined King kills Kog'Maw under two Karthus — twelve damage on demand

4 cards · chaos + order · verified

Pieces

• Kog'Maw, Caustic ×1 OGN-190 · payoff · chaos

  [Deathknell] — Deal 4 to all units at my battlefield. (When I die, get the effect.)

• Blade of the Ruined King ×1 SFD-178 · enabler · order

  [Equip] — 1 Order Power, Kill a friendly unit (Pay the cost: Attach this to a unit you control.)

• Karthus, Eternal ×2 OGN-236 · engine · order

  Your [Deathknell] effects trigger an additional time.

Payoff

Deck

• Legend domains must cover Chaos (Kog'Maw) and Order (the Blade, both Karthus). There is exactly ONE Order/Chaos legend NAME in the pool — Heart of the Tempest — printed under TWO base codes, VEN-155 and VEN-197. Counted from data/cards.json by base code and by name, not from a grep row: this is the tightest identity of any entry in this walk and it means the shell is fixed before the first card is chosen.

Prerequisites

• TWELVE DAMAGE, FIRED WHEN YOU CHOOSE. 1 Deathknell + 2 Karthus = 3 executions of 'Deal 4 to all units at my battlefield' (R1 = A with stacking), and the kill is the Blade's own [Equip] cost — 428.1 defines Killing as 'the action of a Permanent going to the trash from the board' and 428.1.a.1 admits it 'as a cost for a card or ability'. No combat, no attack, no timing window to be denied.
• IT IS SYMMETRIC AND KOG'MAW IS THE ONLY BODY YOU SHOULD HAVE THERE. 'All units at my battlefield' includes yours. He is Might 1, so walk him alone to the battlefield you want cleared — 144.4.a moves him base-to-battlefield for his own exhaust (144.2), and at 1 Might he survives nothing anyway. The Blade's bearer must be a DIFFERENT body you keep, since the cost kills one friendly unit and the gear attaches to another.
• Twelve clears almost the whole pool in one instruction: the largest printed unit Might is 12 (UNL-059 Master Yi, Unstoppable, UNL-147 / UNL-238 Baron Nashor) and 143.2.a needs damage equal to a unit's Might to kill it, so a garrison of anything smaller dies entire. A body wearing a Might Bonus (137.3, largest +4) can survive.
• ONE SHOT PER KOG'MAW AND PER BLADE. The Blade's [Equip] is what pays the kill, so each copy of the gear buys one firing; 103.2.b caps both at three, giving three wipes a game. It is repeatable-removal in the vocabulary sense, not an engine that ticks — and the entry says so rather than implying a loop.
• The Karthus pair is the same doubling karthus-machine-evangel-renata-plaza and karthus-honest-broker-blade-gold already run, pointed at damage instead of tokens; with one Karthus it is 8 and with none 4, which kills far less. Both Karthus are 3-Might bodies that need to survive, and they may stand anywhere — his ability has no location clause.
• Cost, counted whole: Kog'Maw 3 Energy + 1 Chaos Power, the Blade 3 Energy + 1 Power to play and 1 Order Power to [Equip], two Karthus 6 Energy + 2 Order Power. 12 Energy and 5 Power, spread over turns.
• Rider outside uses: UNL-145 Pyke, Returned ('Once each turn, when an enemy unit dies while I'm at a battlefield, play a Gold gear token exhausted') is Chaos and on identity, so a wipe at his battlefield also pays a Gold — once, because of his own 'once each turn'.
• ONE ENERGY AT REACTION SPEED ANSWERS THE BODY THIS ENGINE STANDS ON (Kog'Maw, Caustic (M1 x1)). OGN-133 Flurry of Blades is Body, 1 Energy: "[Reaction] (Play any time, even before spells and abilities resolve.) Deal 1 to all units at battlefields." 143.2.a kills a unit whose marked damage equals or exceeds its Might and 142.4.b defines Lethal Damage as "a non-zero amount greater than or equal to that Unit's Might", so one damage is lethal to every body of Might 1 or less. RUNNING MORE COPIES IS NOT A DEFENCE: 370.1.a.2 makes events simultaneous when they "are all the result of the same Game Action", so the sweep kills every copy at once. And because it carries [Reaction], 813.1.c.1 lets it be played "during Closed States on any player's turn" - it never has to be cast a turn early the way the base-reaching removals do, and it can land in response to the very trigger this engine exists to fire. WHAT PROTECTS IT: this identity is fixed at chaos+order, so the following is the whole of what 103.1.b allows. already in this identity: OGN-243 Darius, Executioner ('Other friendly units have +1 Might HERE' - his battlefield only, and never himself); OGS-013 Garen, Commander (same clause as Darius, same limits) | colourless, so legal whatever the second domain is: OGN-294 Trifarian War Camp (colourless battlefield, 'Units here have +1 Might') - but 485.5 makes a battlefield you bring a 1-in-3, and 103.4.c forbids two of the same name. A single-target pump is no use against a sweep that hits every body at once, which is why only permanent, board-wide sources are listed.

Steps

1. Board over the preceding turns: two Karthus, Eternal, a body to carry the Blade, and Blade of the Ruined King in hand.
2. Walk Kog'Maw, Caustic alone to the battlefield you want cleared (144.1.a, 144.2, 144.4.a).
3. Activate the Blade's [Equip] for 1 Order Power, attaching it to the body you are keeping and paying the kill half with Kog'Maw (428.1, 428.1.a.1).
4. His [Deathknell] runs three times — his own plus one per Karthus: 4 damage to all units at that battlefield, three times over.
5. Twelve damage is marked on each of them (143.3); anything with Might 12 or less dies (143.2.a).
6. The Blade stays attached at +4 Might on its bearer (137.3). Repeat with the next copy of each.

How it ends

engine — a twelve-damage sweep of one battlefield, three times a game, at a time of your choosing

Sources

Walked here, in this project

• Walk of the unwalked partners of the 66 proven synergy rules, rules blade-of-ruined-king-deathknell-ondemand and karthus-deathknell-double 2026-09-06 record

Walked against Core Rules 2026-07-16

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