Add the regen mana on spell casted, and set initial mana to 0. Closes #15460 (cherry picked from commit da612f2041b15bb6f19cee01bd201d63e304d4dc)
Add the regen mana on spell casted, and set initial mana to 0. Closes #15460 (cherry picked from commit da612f2041b15bb6f19cee01bd201d63e304d4dc)