First of all, we need to know that the mysterious Olympic Games is a team of four Otto soldiers from its name. However, I believe all the audience know who they are. They are the kings of Noah Altman, Reggie Altman, Sega Altman and Otto. As we all know, their four Otto soldiers were once the strongest in the universe, and they were introduced in the setting. In a word, Wheel Valley Company recognizes that they are the strongest Otto soldiers in the universe. In fact, the mysterious four Olympics exist because they are all linked by one. If they have the first reason, they will have the second reason. I believe many viewers have found the reason in the plot.
Secondly, why are they called the four mysterious Olympics? The first reason is that they rarely appear in the plot. As we all know, Noah Altman only appeared twice in the plot, while Reggiot's box Sega Altman only appeared once. The king of Otto played the most times. Although the King of Ott appeared the most times, he rarely appeared in the plot. It can even be said that no audience and Otto soldiers have seen the true face of the King of Otto (so far this is why they are called the mysterious four Olympics. If they don't appear often, they will be mysterious. There are also reasons that affect their less appearances. As I said just now, their strength is the strongest in the universe. They are the four strongest Otto fighters in the universe. This is the reason why they play less. Their power is too strong. As long as they appear, it is the rhythm of seconds kill, and there is nothing to see at all, so they will appear less.
Finally, to put it bluntly, this is just the setting of four Otto soldiers. Occasionally appearing once or twice in the plot will also bring good results to the plot. It is because those super Otto soldiers occasionally fight monsters that the scene is very shocking and helpful to the ratings.