The return of the Poison Counters in Phyrexia: All Will Be One has been contentious, especially in the Commander format. If any player gets 10 Poison Counters they lose the game. This increases the pace of gameplay dramatically, although you do risk making yourself the archenemy of your table by using the strategy. While Poison certainly has some detractors, the mechanic is also quite popular, as evidenced by the recent price rise of this Poison Counter generating card.
Phyresis Outbreak

Phyresis Outbreak

For two and a Black,
Phyresis Outbreak


Poison decks can sometimes run into difficulty, as they can rush one player down, and then get taken out by the rest of the table. This often does not lead to a very fun social experience, as the player who gets rushed can feel resentful towards the Poison player, and the Poison player can then feel ganged up on by the rest of the table. Spreading the Poison to multiple opponents also works great with both of the Commanders from the Corrupting Influence Precon
Ixhel, Scion of Atraxa

Corrupted — At the beginning of your end step, each opponent who has three or more poison counters exiles the top card of their library face down. You may look at and play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast those spells.
and
Vishgraz, the Doomhive

When Vishgraz enters, create three 1/1 colorless Phyrexian Mite artifact creature tokens with toxic 1 and "This token can't block."
Vishgraz gets +1/+1 for each poison counter your opponents have.
, both of whom benefit from having many Poison Counters in play, with Ixhel specifically wanting each opponent to have three or more.
Phyresis Outbreak

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