| MrCharisma |
Alchemist bombs deal fire damage by default so immunity to fire would render the creature immune to the alchemist's bombs.
Explosive Bomb doesn't change this, so they would stiol be immune.
Acid Bomb, Frost Bomb and Shock Bomb will all change the damage type to a different element. Force Bomb will make it Force damage. Boneshard Bomb and Thorny Bomb make it Piercing damage. There are probably other discoveries that change the damage type but that's all I can think of.
It's definitely worth getting one of these discoveries early on, because Fire resistance/immunity is very common. My alchemist for Carrion Crown took Frost Bomb at level 2 and I was thankful for it very quickly (that's probably a slight spoiler, but I imagine you vould say that about every AP).