This Monster reappeared in the series Ultraman Max.
In Ultraman Max, Red King's subtitle is Vehicle Armor Monster (装甲怪獣, Sōkō Kaijū?) "装甲 (Sōkō?)" means vehicle armour.
Red King was mentioned in a prophecy as a destructive monster who was sealed underground by a race of Pigmon long ago. However several years in the present after the tomb and the last of Pigmon's race is disturbed, Red King awakens from underground and resumes his rampage on the island he is on. Pigmon uses the guardian monsters of the island, Salamadon and Paragura to fight Red King, but Red King easily beats them both down (individually) and eventually kills them both before shifting his attention to Pigmon. Ultraman Max appears and fights Red King and manages to bury the monster underground during their first time before Paragura appeared, but Red King burrowed away to recover. After Red King kills Salamadon and Paragura he tries to kill Pigmon, but Pigmon is rescued by DASH and Ultraman Max returns for a rematch. After a lengthy battle Red King weakens and becomes highly explosive, with this Ultraman Max carries his to the Earth's atmosphere and destroys him with the Maximum Cannon so that way he could detonate without harming Earth.
Towards the end of the series, Red King returns by a dimensional portal that opens up in the middle of Tokyo and is still highly explosive. However his appearance this time around is more comical as is the other villain that appears to have brought him there: Alien Shama. However, Ultraman Max fights back and defeats him again using the Max Galaxy, twice.
In this series, Red King possessed a breath weapon consisting of impact-explosive rocks, similar to Toho's Megalon, except Red King's were a barrage rather than singular. Presumably these were a type of waste material expunged from the intestines, used as an offensive deterrent (much like monkeys throwing excrement) against an attacker. Also his appearance in the series is the most comical as opposed to his other menacing appearances.
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