I've started playing with friends and for spells, the bonus on the hit dice is current focus.
Determine a magic attack's success by making a magic attack roll. Roll 2d6 and add the attacking model's current FOCUS. roll an additional die if the roll is boosted. Special rules and certain circumstances might modify the attack
What does it mean? Is it the remaining focus you have at the time of the spell? And if so, is it counted before or after you spend the focus?
With my warcaster, I have 6 max focus (the number of focus I have at the beginning of the round) after spending some of my focus on my warjacks, I have 2 left available. I decide to cast a spell that costs me 2 focus.
So my bonus to hit is 6, 2 or 0?