Namikaze Minato learned the art of driving Raytheon. Flying Raytheon is a special endurance skill, which is different from other endurance skills. General endurance skills need to be printed, and flying Raytheon skills don't need to be printed. When Muhuoying II invented the flying Raytheon skill, he removed the printing step and put it into a special spell, which is the destination of the flying Raytheon skill.
Where a spell is cast, Huo Yingsi can reach it in an instant by replacing the technology of flying Raytheon, and the place without a spell can't fly. The spell is the seal of flying Raytheon technology. It is impossible for the four generations of Muhuoying to know in advance where to put the spell when fighting. In order to solve this problem, he deliberately added the spell of flying Raytheon to the bitter places, so that these bitter places could fly by flying Raytheon. That's why Raytheon is so strong.
Flying Raytheon is the fastest. Only the second generation of Muhuoying is almost the same as the fourth generation of Muhuoying. Even if it is almost the same, the fourth generation of Muhuoying is still faster than the second generation of Muhuoying. Muhuoying II admits that it is not the fastest.
Namikaze Minato has a son, Usagi Naruto, who is also very fast. When Naruto moves in Kyubi no Youko's chakra pattern, it is like a golden flash. Kakashi said that seeing Naruto's movements is like seeing his own teacher. Teacher Kakashi is the eye of four generations.
Except Naruto and Muhuoying II, others are not as fast as Muhuoying IV, and no one will be faster than Muhuoying IV in the future.