So, the enemy gunslinger is loading his weapon and the heroic alchemist decides to throw a bomb at him in hopes the gunpowder being used would explode. Same party,the (Wizard/sorcerer/cleric or druid with Fire domain) is casting a spark, or other flaming spell, to target the gunpowder container. How vulnerable is it?
Loading a firearm provokes attacks of opportunity. Can ranged attacks be used for these attacks of opportunity since the Gunslinger is likely to be at range?
Can a gunslinger target an opposing gunslinger to disrupt his loading of the weapon?
It isn't anymore vulnerable than the wizard's spell components he just dragged out or the fighter's arrow or bow string.
No, since ranged attacks don't threaten (with the sole exception of a monk of the zen archer archetype of high enough level).
As it stands no, unless you mean "kill" by disrupt and then yes as being killed does disrupt the loading of a weapon.
It isn't anymore vulnerable than the wizard's spell components he just dragged out or the fighter's arrow or bow string.
So, gunpowder is inert until the gun fires? I understood the idea that an alchemist's bombs are inert until the alchemist completes, or activates, them. But, gunpowder is gunpowder. Unless it's not; that's what I'm wondering.
Can a rogue take gunpowder and pour it on the ground to light with a torch so it is a fuse to cause a pile of gunpowder to explode?
Can an arcane caster use gunpowder as a component/focus to enhance a fireball?
Would a burning ship with a powder magazine for the cannons have a chance of exploding?
If they can then an arcane caster can drop a Flaming Sphere on a gunslinger who is loading her gun and, if she fails her save the gunpowder has a chance to explode.
It isn't anymore vulnerable than the wizard's spell components he just dragged out or the fighter's arrow or bow string.
So, gunpowder is inert until the gun fires? I understood the idea that an alchemist's bombs are inert until the alchemist completes, or activates, them. But, gunpowder is gunpowder. Unless it's not; that's what I'm wondering.
Can a rogue take gunpowder and pour it on the ground to light with a torch so it is a fuse to cause a pile of gunpowder to explode?
Can an arcane caster use gunpowder as a component/focus to enhance a fireball?
Would a burning ship with a powder magazine for the cannons have a chance of exploding?
If they can then an arcane caster can drop a Flaming Sphere on a gunslinger who is loading her gun and, if she fails her save the gunpowder has a chance to explode.
If the gunslinger rolls a 1 on the save, then the gunpowder has that chance, otherwise it is safe. Part of the rules of saves on page 217 of the Core Rulebook.