Seed of Renewal
Seed of Renewal is an Imbuing ingredient needed to imbue the Hit Point Regeneration, Stamina Regeneration and Mana Regeneration properties. It can be found as loot on creatures of the Cavern of the Discarded Mini-Champ.
It has also been noted that it can be grown through Gardening. When collecting seeds from plants, there is a rare chance that a Seed of Renewal drops in your backpack.