Hardy gout tubers are obtained during the My Arm's Big Adventure quest from Murcaily. They can not be dug up or planted in a herb patch. A single tuber is given to the player after obtaining 60% favour, but is immediately replaced a handful of tubers by Murcaily after My Arm goes on a rampage.
They are given to My Arm towards the end of the quest, before the final fight with the Baby Roc and Giant Roc.
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