Regain is a recurring status effect in the Final Fantasy series that restroes TP over time.
Appearances[]
Final Fantasy XI[]
Regain gradually restores TP. There are several ways of attaining Regain, such as the Scholar spell Embrava, or the Monarch Drink, which is a common temporary item in Besieged. Regain granted by the drink adds +3 TP per tick for the duration of the effect.
Final Fantasy XIV[]
Regain gradually restores TP. It was provided by the 
Regain Feather, an item that could be purchased using 
Wolf Marks acquired from PvP. Regain Feathers could only be used in PvP areas that allowed the use of items. With the removal of TP in Shadowbringers, Regain Feathers lost their effect, and it is no longer possible to gain the Regain status, nor would it have any effect.