The rules of the Heavenly, Earthly, and Man Rankings are such that one can challenge others, and each person has one opportunity every year. If you do not challenge anyone this year, then that opportunity will disappear. It cannot be accumulated. Anyone on the rankings can be challenged an unlimited number of times.
This is the truly brutal aspect of the Trial Field!
Everyone desires to be on the rankings, but once listed, they will face endless challenges. This is especially true for those on the Man and Earth Rankings, who nearly each have to face a large number of battles every year.
Therefore, the cultivators on these rankings all possess a heavy killing aura.
Apart from this rule, there is another way to get on the rankings—that is, if you inadvertently defeat a ranked cultivator who is ranked higher than you. Your name will then replace theirs!