Toxo-Viper is a Cobra operative in the original G.I. Joe: A Real American Hero line. First released as a Hasbro carded action figure in 1988, with 2 distinct figure versions produced across the 1982 to 1994 ARAH run.
Toxo-Viper did not appear by name in the Sunbow or DiC cartoon series synopses. Original Hasbro file-card lore and Marvel ARAH comics appearances are the primary characterization sources.