Weasel is John Monroe, a costumed villain and enemy to Firestorm. He was a student of Martin Stein who became a serial killer. The name "Weasel" was inspired by a nickname others had given him. Monroe eventually died on a mission with the Suicide Squad. The New 52 rebooted John Monroe as a more animalistic figure.
The Weasel was created by Gerry Conway and Rafael Kayanan, first appearing in Firestorm (Volume 2) #36 (1985).
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