It is possible to make your consumables heal more health and last longer in Final Fantasy XVI via a potion potency related “The Root of the Problem” sidequest. It doesn’t come up until you’re substantially into the game. However, once it does, talking to Nigel at the hideaway and finding him some morganbeards flowers from Rosaria makes a big difference.
How to increase potion potency via “The Root of the Problem” in Final Fantasy XVI
First, head to the “gardening” area of the hideaway to talk to Head Botanist Nigel. He’ll explain that he needs some morganbeards, a kind of flower that grows in Rosaria, in order to help make the potions healers create at the hideaway stronger. He has a general idea of what they look like and also explains that goblins like them. (This is a hint that you’ll be fighting a lot of goblins during this questline.)
Head to Martha’s Rest on the Rosaria map. You’ll be headed to a designated location in Sorrowise. To be specific, you’ll be getting three morganbeards from the following three spots in the screenshot I took below. (Two are right next to each other. All three are clearly marked by quest indicators… and groups of goblins near them.) Note that on the way, you’ll probably run into the B-rank Notorious Mark Severian.
Take the flowers back to Nigel at the hideaway. You’ll get 350 EXP, 15 renown, a Black Blood, and the Morganbeard Extract “curiosity.” That curiosity is the reason your Final Fantasy XVI potion potency will increase. Potions and High Potions will restore more health, while the Lionheart, Stoneskin, and Strength Tonics’ effects will last longer than before.
However, there’s still one more step to maximize them in a future quest.
Final Fantasy XVI is available for the PlayStation 5. There is a six-month exclusivity period.