Karumonix, the Rat King

As of Jul 23, 2026, the cheapest tracked printing of Karumonix, the Rat King is $0.60 (ONE #282, Foil), and the most expensive is $14.18 (ONE #439, Showcase, Step and Compleat Foil). The benchmark price (cheapest playable nonfoil) is $1.16, up 8.4% over 7 days, up 7.4% over 30 days, up 8.4% over 90 days. All-time tracked high: $1.20 (2026).

Karumonix, the Rat King has 6 tracked printings across 2 sets, in foil, nonfoil and step and compleat foil finishes, including showcase, promo pack and prerelease treatments.

ONE #282 Foil

$0.60

CK $0.99 / $0.25 58%

PONE #98p Promo Pack

$1.16

CK $1.29 / $0.17 85%

ONE #98

$1.21 +4%

CK $1.29 / $0.52 57%

PONE #98p Promo Pack Foil

$1.24 +7%

CK $1.49 / $0.45 64%

ONE #98 Foil

$1.51 +30%

CK $1.49

ONE #307 Showcase Foil

$1.57 +35%

CK $1.99 / $0.60 62%

ONE #307 Showcase

$1.59 +37%

CK $1.29 / $0.65 59%

PONE #98s Prerelease Foil

$3.17 +173%

CK $4.49 / $1.80 43%

ONE #439 Showcase Step and Compleat Foil

$14.18 +1122%

CK $10.99 / $5.50 61%

Card Kingdom currently pays $5.50 cash for ONE #439 (Step and Compleat Foil); the retail-buylist spread on that printing is 50% (wide).

• Feb 4, 2023 A player with ten or more poison counters loses the game. This is a state-based action and doesn't use the stack. In other words, it happens immediately and players can't respond to it, just like a player losing the game due to having 0 or less life.
• Feb 4, 2023 Any other effects of that damage, such as life gain from lifelink, still apply.
• Feb 4, 2023 Conversely, replacement effects that apply to the number of counters put on a player can modify the counters placed this way. For example, Vorinclex, Monstrous Raider's last two abilities can apply to counters placed this way.
• Feb 4, 2023 Damage dealt by a creature with toxic grants the same number of counters regardless of how much damage is dealt. Notably, if a replacement effect modifies the damage in some way (such as that of Gratuitous Violence), the number of counters given remains unchanged.
• Feb 4, 2023 If a creature with toxic deals combat damage to a creature or planeswalker, or if it deals noncombat damage, toxic has no effect and no player gets poison counters.

Karumonix, the Rat King has been reprinted 9 times.

Set	Date	Rarity	Treatment
ONE #307	2023-02-10	Rare	Showcase
ONE #307	2023-02-10	Rare	Showcase
PONE #98s	2023-02-10	Rare	Prerelease
PONE #98p	2023-02-10	Rare	Promo Pack
PONE #98p	2023-02-10	Rare	Promo Pack
ONE #439	2023-02-10	Rare	Showcase
ONE #282	2023-02-10	Rare	Standard
ONE #98	2023-02-10	Rare	Standard
ONE #98	2023-02-10	Rare	Standard

Karumonix, the Rat King is the #3,303 most-played card on EDHREC, down 19 places over the last 30 days.