Phenomena Points are a special reserve that Druids can draw from in order to power their most awesome of abilities, known as Wonders and Calamities. The points regenerate at a rate of approximately two or three per minute, up to a maximum amount determined by the character's level (somewhere between 10 and 60 points).
It is unknown if Vitality affects the slow regeneration rate of Phenomena points, but the ability Heirophant's Boon can be used to instantly refresh their reserve at times of need.