Count to 10 for the win.
I very recently talked about the problem with Infect in Commander. In general, the downsides of trying to poison the table down are greater than your shot at actually successfully counting to ten for the entire table. However, with the new Commander precon, Corrupting Influence, focusing on the Toxic variant of the mechanic, a lot of players will be trying anyway.
Phyrexia: All Will Be One Commander Deck – Corrupting Influence
Commander: Phyrexia: All Will Be One
I won’t stop you, and I’ve been known to try and get some infect wins myself. That means the least I can do is recommend the best of Infect for your deck. I’ll only be focusing on cards that use the Infect keyword themselves, as opposed to other sources of poison or proliferation, since those essentially deserve a list of their own.
#10 Core Prowler
Mirrodin Besieged, Uncommon
Something of an oddity to start the list off with, Core Prowler is here almost exclusively because of its combo potential. If you can get in with it once (or with any other source of poison counters) you can then use its death trigger to close out of the game. With the right combination you can loop Core Prowler with Reveillark, Karmic Guide, and a sac outlet, netting plenty of proliferation after the initial infection.
#9 Flesh-Eater Imp
Mirrodin Besieged, Uncommon
The best Infect cards can get the job done on their own. Core Prowler is a combo piece that only has to see one poison counter to kill, and Flesh-Eater imp only asks that you have enough snacks to count to ten. If you can make a lot of tokens (say, Mites), Flesh-Eater Imp can become as big as an Eldrazi-— an Eldrazi that can instantly end the game for someone.
#8 Phyresis
Mirrodin Besieged, Common
Giving a card Infect that wouldn’t normally have access to the keyword is where the real gold is if you want to down the table with poison. Phyresis does it simply, transforming pingers like Syr Konrad, the Grim into potentially lethal threats. The rare version, Glistening Oil does the same recursively, but slowly shrinking our creatures will often feel bad and can backfire.
#7 Corrupted Conscience
Mirrodin Besieged, Uncommon
Corrupted Conscience might be the most slept on Mind Control variant in the game, stealing a threat and making it even more dangerous than usual. If you have opponents who like running giant threats, Corrupted Conscience can turn their would-be win conditions into yours. In a pinch, it also works as another (too expensive) Phyresis for your own creatures.
#6 Skithiryx, the Blight Dragon
Double Masters, Mythic
A large, evasive beater with Infect is one of the last things most will expect, so Skithiryx (popularly nicknamed Skittles during its stint in Standard) can be quite the surprise. Tack on the ability to gain haste and protection with Regeneration and you have quite the poisonous package. Bonus points for being an option for the command slot, though I wouldn’t particularly recommend trying to run mono-black infect (trust me, I tried).
#5 Blighted Agent
New Phyrexia, Common
The vast majority of Infect creatures are almost laughably small and need buffs to actually do anything. Most of those can also be chump blocked or easily removed. Blighted Agent has only one of those problems, and is easily the best option to start infecting players if your end game is to Proliferate up to 10. Or, suit him up and watch players scramble for answers.
#4 Tainted Strike
Scars of Mirrodin, Common
Once again, giving Infect to creatures that normally wouldn’t be seen anywhere near a Phyrexian is where the mechanic shines. Take a large double striker, like say Blast-Furnace Hellkite, and suddenly someone is dead with the help of Tainted Strike. Knocking a player out suddenly is a memorable experience, so don’t expect the poisoned player to forget either.
#3 Blightsteel Colossus
Double Masters, Mythic
Creatures that can win with one swing are a relative rarity, but Blightsteel Colossus can pull off quite the Phage the Untouchable impersonation. Unlike Phage, however, you can cheat Blightsteel out with cards like Show and Tell or the new transformer Ultra Magnus, Tactician to brutal effect. Another one-card win condition puts this Golem high on the list.
#2 Grafted Exoskeleton
Scars of Mirrodin, Uncommon
Look at that, another way to gift Infect to creatures. This one sticks around to do it multiple times (without shrinking them like Glistening Oil), and even provides a bonus buff as long as you don’t mind the risk of sacrificing the creature. With the added buff, this card also goes great in a Voltron package or any kind of Xenagos, God of Revels style beatdown deck. Easily one of the best Infect options available, period.
#1 Triumph of the Hordes
New Phyrexia, Uncommon
The poster child for winning with Infect in the format, Triumph of the Hordes is very high on peoples list of saltiest cards for a reason. Like the other cards that grant Infect, this card can represent a “one-card” win con, but spreading it across your entire board means you can potentially crash in for 10 for every player instead of just one. If your board goes even moderately wide this card can win so easily it almost feels like cheating. Almost.