Gyeron Starbem is a popular ultraman monster, despite appearing only in one episode of Ultraseven.
Despite warning, a large cannon called the Super Weapon R1 is fired into a desolate planet. Not long after scanners get readings of some radioactive life form comes to earth, in the form of Gyeron. His goal was to get blood thirsty revenge against earth for destroying his home world. After wreaking much havoc in Japan, he is blown to bits by military weapons, but reforms later that night and continues his rampage. After much destruction, Ultraseven was called into action and came into battle, only to realize that his hits did no damage to Gyeron, so he rips off Gyeron's wings causing him to scream loudly in antagonizing pain. Then Ultraseven pushes Gyeron over and slits his throat, causing him to die slowly of blood loss. It is possible that Ultraseven didn't know why Gyeron attacked and that is why he was so relentless. Eventually when he found out the truth about Gyeron, he would have been very guilty.
- There are several toys of Gyeron.