Ultraman Wiki:ParentPage

Q: "Why is Ultra Q the first Ultra Series when it has no Ultraman?"
A:

Q:"Did Godzilla ever fight Ultraman? I keep hearing debates about it, but did it ever really happen?"
A: Well technically, yes and no. There have been two close instances of this, but no official fight has happened between the King of the Monsters and the Heroes from the Land of Light. The first was the monster Jirass from the original Ultraman series, which was a recycled Godzilla suit brought out of storage and modified with a frilled lizard collar to act as a monster opponent.

Another instance was in an episode of Ultraseven, amongst a montage of memories the hero had of his adventures on Earth, viewers could hear the roar of the famous monster, implying that Ultraseven once fought Godzilla off-screen. (This was most likely not shown due to legal issues with Toho.)

Q: "What's with the blinking Christmas lights on their chests?"
A: Those lights are Color Timers, they act as an Ultra's energy gauge and warns them of when their energy is running low. Depending on the series, it acts as a time limit to how long an Ultra can fight on Earth (Usually 3-5 minutes), or as a stamina gauge which blinks when they take too much damage or use too much energy. If the blinking stops, one of two things can happen, the Ultra retreats back into their human host before their energy dries up or if it stops completely, they die.

While the time limit may seem ridiculous to western audiences, it is a weakness which keeps the main hero from being too powerful and adds extra danger to the show by having the possibility the hero could lose against their foes. Plus, from a pseudo-scientific standpoint, it makes sense that an extraterrestrial lifeform would be unable to survive in Earth's environment for very long.

Q:"Are Fire Man, Mirror Man, Aizenborg and Jumborg Ace Ultramen?"
A: No, those shows are separate from Ultraman but utilize a similar show formula and are made by the same company.