Grogg is a fictional monster character from the Marvel Universe who first appeared in Strange Tales vol. 1 #83 (April 1961).
Grogg is a giant who possesses super-strength, can fly and also breathe flames. He lived below the surface of the former Soviet Union but was revived and freed by atomic bomb testing under Colonel Vorcutsky. Grogg pursued all those involved with testing and fought off communists. He then relocated to Earth's moon but later returned to Earth. Miklos Kozlov, a scientist/political prisoner sabotaged the Soviet's plan to build a military base on Mars by tricking Grogg into entering their ship, Kozlov escaped using a smoke screen, leaving Grogg captured and trapped where he was allegedly sent to Mars. Through unknown means he returned to Earth and was captured by S.H.I.E.L.D. where he was placed in that organization's Paranormal Containment Unit.
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