Weezing

Toxic 2
Wither

Smog - if this creature is targeted by a source an opponent controls, that player gets a poison counter.

Corrupted - whenever this creature deals combat damage to
a player, if they have three or more poison counters, place a polluted counter on target land that opponent controls that doesn’t have one already. It gains “every time this land is tapped for mana, its controller gets a poison counter.”