What is Fervor?
Ferver has one purpose, and that is to allow you to pick one of any max talent for any of your heroes. This requires 1000 Fervor and can be accessed by clicking on the ‘Talent’ button next to the fervor bar once it is lit up. Assuming average luck, which should be pretty consistent given the 1000 fervor price, it would take around 166 resets to build 1000 fervor, or half that amount when combined with the blessing
How do you get Fevor?
Everytime a talent set is reset either with a Talent Refreshment Bead or 200 Jewels you will receive a random amount of Fervor. The average amount of Fervor received seems to be 6, with the lowest amount being 2 and the highest 20. There is also a Trevi FountainBlessing which doubles the amount of Fervor you receive on your next 50 talent resets