The 1970s was a bit of a «lawless» time in the world of comic books, so unregulated in fact that Mantis of the Guardians of the Galaxy was actually written into comics under 4 different publishers by her creator Steve Englehart. Mantis, or the «Celestial Madonna,» has always been much more cosmically important in Marvel Comics than in the MCU, so important that Englehart brought her into DC, Eclipse, and Image Comics!
Raised in a Kree-worshiping religious sect called The Priests of Pama, the martial artist and superheroine Mantis debuted in 1973's The Avengers #112, introduced as a half-Vietnamese, half-German woman with incredible fighting skills and a tendency to refer to herself in the third person. Originally created by Steve Englehart, known for legendary runs on Green Lantern, The Avengers, and Doctor Strange, the author used Mantis as a major character throughout his run on The Avengers, and loved the character so much that he decided even Marvel Comics couldn't contain her.
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While the green martial artist characters Englehart placed into future comics never explicitly call themselves Mantis, he has officially confirmed that it was his intention that they were all intended to follow Mantis along her journey of motherhood. The end of Englehart's tenure on The Avengers concluded with the massive «Celestial Madonna» story, framing Mantis as the destined mother of the «Celestial Messiah,» sired with the Prime Cotati, a plant-life being with long-held ties to the Kree and Skrulls. Mantis' story ended with her going off with the Prime Cotati who was inhabiting the body of her ex-Avengers teammate the Swordsman to become pregnant and bear her
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