hmmm...I'm not so sure they stack, unless, they are from different sources. For example, Aim (+10%) is the Attack/Action bonus. You cannot
stack All Out Attack on this because, as the RAW states, "A character that takes a full action
cannot take any half actions this round" (pg. 126).
Pg. 127 further states, regarding Aim, "If the character’s following action is a standard attack
, he gains a +10% bonus to Weapon Skill (for melee attacks) or Ballistic Skill (for ranged attacks)." Here, Standard Attack should be capitalized. A Standard Attack is a Half Action.
In the example +Gabriel Gomes
provides, a Ballistic Attack does not really make sense in context of an All Out Attack. How is the Arrow "imbued" with more force after the act of aiming, as +Ian Howard
and +Ben Scerri
And I would argue that even in a pure Melee attack, one cannot stack the Aim and All Out Attack. I liken the Aim and Standard melee attack, both half actions, more like a "called shot to the nuts." Perfectly legit. We can note the RAW for the All Out Attack calls out Melee in context and cites only the Weapon Skill as being modified:The character makes a furious melee attack, exposing himself to danger in order to land a forceful blow. The character’s melee attack gains a +20% Weapon Skill bonus.
Now, when do modifiers stack? For example when Aiming at an Unaware opponent (+30%). Is that 40%? or 30%?. I can't find the specific RAW that limits, or caps, bonuses to +30%, but I will stipulate that there is a common "limit" in test difficulties—even in most
cases with Skills and Talents—that the underlying math of the system suggests +30% is an upper limit. But there are exceptions to that math to be found.
Where there are exceptions, I say, +40% is fully permissible and I too would allow the stacking of Aiming at an Unaware opponent.