Swamp Thing, a imaginary character, is a humanoid/plant creature essential in the DC Comics Universe, created by writer Len Wein and artist Berni Wrightson. Swamp Thing has had a number of humanoid or monster incarnations, based on different story lines. He first came out in House of Secrets #92 (July 1971) in a stand-alone terror story set in the early 20th century. The character then went again in a solo series, set in the modern world and in the general DC continuity. The character is a humanoid mass of vegetable matter that fights to defend his swamp home, the environment in general, and humanity from a variety of supernatural or terrorist risks.