21 cards where the text includes “infect” and the set is “mbs”

Blightsteel Colossus (Mirrodin Besieged #99)
Blightwidow (Mirrodin Besieged #77)
Burn the Impure (Mirrodin Besieged #59)
Core Prowler (Mirrodin Besieged #103)
Corrupted Conscience (Mirrodin Besieged #22)
Flensermite (Mirrodin Besieged #41)
Flesh-Eater Imp (Mirrodin Besieged #42)
Inkmoth Nexus (Mirrodin Besieged #145)
Phyresis (Mirrodin Besieged #49)
Phyrexian Crusader (Mirrodin Besieged #50)
Phyrexian Digester (Mirrodin Besieged #120)
Phyrexian Hydra (Mirrodin Besieged #85)
Phyrexian Juggernaut (Mirrodin Besieged #121)
Phyrexian Vatmother (Mirrodin Besieged #52)
Plague Myr (Mirrodin Besieged #125)
Priests of Norn (Mirrodin Besieged #16)
Rot Wolf (Mirrodin Besieged #90)
Scourge Servant (Mirrodin Besieged #54)
Septic Rats (Mirrodin Besieged #55)
Tine Shrike (Mirrodin Besieged #17)
Viridian Corrupter (Mirrodin Besieged #94)

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