I don't know if you have found that in Ultraman, only a very small number of Ultraman will die, and these dead Ultramans either have no background or go down a dark path. So why can't Ultraman die?
The original Ultraman was a slain Ultraman who was crushed by Jayton in all directions while fighting Jetton. Later, the Speicher Beam was fired, only to be bounced back by Jetton, and the red indicator light fell with a sharp bang. The myth of Ultraman's invincibility is thus broken. After this, the wave of Hippolyte stars disappeared, and I believe many fans still remember it. With their glass cover, the Hippolytes first destroyed the five Otter brothers, and the father of Otter came to Earth for thousands of miles, only to fall due to lack of energy.
There are many more Ultraman deaths like this, with Zoffitello being pecked to death by Patton and Diggardina petrified to death. However, these Ultramans have been active in front of everyone's eyes until now. So, how did they do it.
First Ultraman controls life. This was the earliest setting. Zofi sees the death of the first Ultraman and then uses subspace to start a dialogue with the first generation, saying that he has brought two lives. After many negotiations, one was given to the first generation and one to Hayata. The first generation later came to the Land of Light with Zofi.
The second one is because of the medical skills of Ott's mother. The Mother of Otter is the commander of the Silver Cross Army in the Land of Light, and is a healer. Tyro Ultraman was pecked to death by Patton, and Father O's father was killed by hippolytes, both of whom were saved by Otter's mother. Even the armor of hatred on Shikari's face was removed by him.
The third one is because of absolute power. Leo Ultraman once caught the Disc Creature's trick, resulting in his capture. Later, it was dismembered and buried. Later, Leoto dreamed of Giving Xiao Tong and found the place where the body was buried. The King of Otter appears in time and uses the King's Regenerative Ray to resurrect Leo Ultraman. You know, O'Wang can restore the entire universe, and one life is not a problem in front of him.
The fourth because of weapons. The Ultraman family has a lot of weapons, and the weapons have magical powers. Jack Ultraman's Otter bracelet is one of them. While fighting the Snow Maiden, she was killed by her, and later, Otter's bracelet flashed, and then Jack's body began to fuse and then resurrected.