Gigan is an alien cyborg kaiju best known as the ultimate weapon of the M Space Hunter Nebula Aliens. He first showed up in the 1972 film Godzilla vs. Gigan, where he and King Ghidorah invaded Earth to help conquer the planet. The two monsters tore through Tokyo before getting pushed back into space by Godzilla and Anguirus.
The Nebulans weren't done with Earth, though. The following year in Godzilla vs. Megalon, they sent Gigan back to team up with Megalon and their allies the Seatopians. That didn't go well either—Godzilla and Jet Jaguar sent him packing again. Around the same time, the TV series Zone Fighter showed Gigan under different management, controlled by the Garogas as one of their Terror-Beasts. He fought Godzilla once more before Zone Fighter finally took him down.
After nearly 30 years away, Gigan returned for Godzilla Final Wars, this time working for the Xiliens. He fought Godzilla in Antarctica, got upgraded after his defeat, and came back to aid Monster X in the climactic Tokyo battle. Mothra ended up sacrificing herself to destroy him once and for all.
His early appearances may not have been critically beloved, but Gigan stuck around in fans' minds and became a recurring presence in comics and video games. Director Ryuhei Kitamura actually counted him among his favorite monsters, which helped secure Gigan a spot in Final Wars. That popularity led to two short films in 2022—Godzilla vs. Gigan Rex and Fest Godzilla 3: Gigan Attacks—marking his 50th anniversary debut.
Content compiled by AnimeList.moe from publicly available sources.