Examine the Sluice Gate again to enter the secret hideout.
Examine the Inconspicuous Barrel to receive the Founder king's orb to complete this mission.
According to Balamor, the orb Iroha gave you has something to do with the power of time. He will return what he took from you if you bring him a relic of the founder king. Look for it somewhere in Rala Waterways.
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