Ad aspera

Does triggering the "Mastery" skill from the armor skill tree count as a dodge for abilities that allow for counterattacks? What is the duration of the fire ring? Does the opponent take damage automatically, without the possibility of a defensive roll? Is the ring stationary or does it move with the caster? If there are opponents within a 5-cell radius around the caster, do they automatically take damage? Do characters who have completed their turn within the wall of fire take damage at the beginning of their next turn?