I've had past discussions on this topic with experienced GMs whom I respect, and there is not a complete consensus but a leaning towards including modifiers for passive values. In my opinion, the
ARPG book is not clear, and it could be interpreted either way. It was probably obvious to the original author of the rule set, but the book's wording doesn't make it crystal clear to everyone. (Yes, I'm a computer programmer who's also used to letter-of-the-rules arguments in different game systems.)
My own interpretation is that it seems ridiculous for general modifiers to not affect both Passive values and Active checks. Suppose a guard has a "+5 bonus to all Perception Action Rolls" (with the wording generally given in skill bonuses. Should the +5 occur only for making an active roll and not for passively guarding? Suppose a warrior has a "+2 to all Might Attribute Action Rolls". Should the +5 occur only for making an active dice roll and not for passively checking strength? Suppose a wizard has a "+4 to all Arcanum (Sorcery) Skill Rolls". Should the bonus apply when rolling dice (such as to hit with a spell or to see whether a spell is successfully cast) but not when using passive values (such as seeing about meeting the CTN for automatically casting a spell without a roll or to check on
unraveling the thread [dispelling] that self-same supposedly powerfully cast spell)? To me, doing one but not the other seems weird and contradictory.
But we have another set of wording beyond the
ARPG hardback. I checked the old Shattered Empires Quickstart rule book, and its wording is more explicit than the final rule book. To quote the rules from pages 62-63:
Quote:
Passive Action Rolls
Sometimes an Action Roll is needed to overcome the efforts of an unaware or absent character. In such cases, the Action Roll has a TN equal to the opposing character’s modifier plus 12. This system works in a manner similar to defenses (see Combat) and can govern many situations where an opposed check would be suitable, except that one or both parties are unaware of the contested action.
EXAMPLE: A character may wish to sneak past a distracted guard. Rather than slow the pace of game play with a series of dynamic Action Rolls the character performs an Action Roll against the guard(s) Perception skill (and other modifiers) + 12. This system could also be used to defeat traps set by a skilled artisan, to spot a forgery, decipher a code, or any other situation one may imagine.
That seems to imply that all modifiers to the guard's Perception skill apply to the passive as well as active skills. It also states (as does the
ARPG) that the point of passive is to reduce the need for lots of die rolling, and thus a modifier for one should apply to the other--unless explicitly stated otherwise.