by liahgeron » Fri May 02, 2014 8:45 pm
"The Expose effect is followed by one trait. If you have that trait and are subjected to this effect, you must cry out, revealing the fact that you have the trait and revealing your position. You must cry out as loudly as the Expose effect was called."
-Core Rules for Expose
"This effect is used to determine if the recipient is inflicted with a specific effect, trait, or game condition...To use Diagnose, touch the recipient with a packet and say "Diagnose" followed by an effect, trait or game condition."
-Core Rules for Diagnose
So, Exposes are a bit of an odd call in accelerant. Expose is typically used for character traits like "Human" or "Cyborg" or "Demon." It is almost always delivered "By my voice." It can also be delivered "By your Name" to find someone. It can also be considered similar enough to an AOE Diagnose call with a bit of added functionality. This has been primarily used for "By my Voice, Expose Unstable" as a mass triage effect since you have the trait "unstable" when you have gone down to called damage. Expose is also not a beneficial effect and you call out obviously to everyone nearby.
Diagnose originally was used to determine if someone has a trait or is under an effect (stun, silence, maim, paralyze, etc). Though not explicitly stated, the response to a Diagnose is usually considered only to be known to the person who used the effect. As nearly all diagnoses are touch cast, they can also be refused as per the no contact rule. Many games choose to interpret Diagnose to also include the trait of the delivered effect. For example, if Bob had been set on fire via an "Agony by Fire," he would respond "yes" to "diagnose agony" or "diagnose fire."
Combining this with the interpretation of Expose as an AOE diagnose (which appears to be the intent here, though for ranged instead of AOE), you can craft an "Expose Fire" that he would also call out to revealing him to be obviously on Fire to all present. This has some limited functionality if you want to rapidly triage a group hit with an AOE or reveal that someone is under some sort of potentially behavior altering effect (like frenzy, most imbues or inflicts won't ping to a diagnose unless otherwise stated) with an expose packet, but otherwise not the most useful for revealing the Demons in your midst. I would guess that you could dump the appropriate research into it though and possibly get an item to do what you are interested in... but that might take allot of study. On the other hand, Expose Disease could also be potentially useful in some cases I imagine. Immediately informing everyone there that the target is diseased might have a better effect than diagnosing them then having to shout about your results.