It all started when 7 young nobles suddenly woke up to the fact they were utterly dispensable and even undesirable to their powerful noble house - the Cin House.
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There were four major reasons for noble families in a Boundless Transcendent World to have a very large number of sons specifically, not just large numbers of children, and some noble families even had a system of secret heirs.
The first was simple elimination by Heavenly Tribulations.
When their children tried to cross into higher Great Realms, in case of the Wei Dynasty, the Seven Profound Realms, it was expected to lose as many as a third to the trial of the Heavenly Daos - and truly unlucky families could even lose up to half.
The second reason was natural elimination.
