23 cards where the illustration contains “necrogen-vent”

Blackcleave Cliffs (Phyrexia: All Will Be One #248)
Blackcleave Cliffs (Phyrexia: All Will Be One #370)
Bringer of the Black Dawn (Fifth Dawn #43)
Chimney Imp (Mirrodin #59)
Darkslick Shores (Phyrexia: All Will Be One #250)
Death Cloud (Darksteel #40)
Flayer Husk (Mirrodin Besieged #107)
Moriok Rigger (Fifth Dawn #54)
Necrogen Scudder (Scars of Mirrodin #71)
Nim Deathmantle (Scars of Mirrodin #188)
Pierce Strider (Mirrodin Besieged #123)
Plague Stinger (Scars of Mirrodin #75)
Possessed Portal (Fifth Dawn #144)
Swamp (Phyrexia: All Will Be One #274)
Swamp (Scars of Mirrodin #241)
Swamp (Mirrodin #298)
Swamp (Phyrexia: All Will Be One #264)
Swamp (Phyrexia: All Will Be One #367)
Swamp (Jumpstart #58)
Swamp (Magic Premiere Shop 2010 #3)
Swamp (Arena League 2004 #3)
The Dross Pits (Phyrexia: All Will Be One #251)
Vault of Whispers (Mirrodin #286)

The message was clear to Sorin—time to search for something else.