Cankerbloom

Public decks that run Cankerbloom

• Corrupting Influence - Phyrexia: All Will Be One Commander, led by Ixhel, Scion of Atraxa

Commanders that run Cankerbloom most

Deck counts from EDHREC.

• Atraxa, Praetors' Voice: 15,017 decks
• Meren of Clan Nel Toth: 10,386 decks
• Fynn, the Fangbearer: 9,253 decks
• The Wise Mothman: 5,787 decks
• Auntie Ool, Cursewretch: 5,619 decks
• The Mycotyrant: 5,592 decks
• Ixhel, Scion of Atraxa: 5,056 decks
• Muldrotha, the Gravetide: 4,056 decks

Often played with Cankerbloom

Cards that show up in the same decks on EDHREC.

• Kuldotha Cackler
• Forgehammer Centurion
• Urabrask's Anointer
• Axiom Engraver
• Magmatic Sprinter
• Churning Reservoir
• Cinderslash Ravager
• Free from Flesh
• Furnace Strider
• Exuberant Fuseling

Rulings

• 2023-02-04: You don't have to choose every permanent or player that has a counter, only the ones you want to add another counter to. Since "any number" includes zero, you don't have to choose any permanents at all, and you don't have to choose any players at all.
• 2023-02-04: Players can respond to a spell or ability whose effect includes proliferating. Once that spell or ability starts to resolve, however, and its controller chooses which permanents and players will get new counters, it's too late for anyone to respond.
• 2023-02-04: To proliferate, you can choose any permanent that has a counter, including ones controlled by opponents. You can choose any player who has a counter, including opponents. You can't choose cards in any zone other than the battlefield, even if they have counters on them.
• 2023-02-04: If a player or permanent has more than one kind of counter on it, and you choose for it to get additional counters, it must get one of each kind of counter it already has. You can't have it get just one kind of counter it already has and not the others.
• 2023-02-04: An ability that triggers "Whenever you proliferate" triggers even if you chose no permanents or players while doing so.
• 2023-02-04: If a permanent ever has both +1/+1 counters and -1/-1 counters on it at the same time, they're removed in pairs as a state-based action so that the permanent has only one of those kinds of counters on it.