The original Stinkweed Imp appeared in Ravnica: City of Guilds, in 2005.
The original art was by Edward P. Beard, Jr..
Time Spiral Remastered
The List
GRN Guild Kit
Duel Decks Anthology: Divine vs. Demonic
Modern Masters
Duel Decks: Izzet vs. Golgari
Ravnica: City of Guilds