Spartans tested their youth by having them go to the countryside and kill slaves!

Krypteia was a tradition for young Spartan men as a part of their education. Young Spartan men who had completed their training with success and had shown the potential to be future leaders would be given the opportunity to test their skills and prove themselves worthy of the Spartan military tradition through participation in the krypteia.

Every autumn, war would be declared on the Spartan slaves so that any Spartan citizen could kill a slave without fear of blood guilt. Reasonably, many slave owners did not want their slaves to be killed and would thus punish those who killed them. As part of the krypteia, the aforementioned young Spartan men would be sent into the countryside with the instruction to kill any slave they might encounter at night without punishment.

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