Starr blinked. "Uh. I wouldn't say immune, no."
Stadium on fire, gunshots, running, screaming.
She shook her head. "But like, any mon worth their salt is gonna be strong enough to tank a few hits and turn a human into paste before you blink, you know? Yeah, they'll bleed, but like... unless you've got a really lucky shot, it's usually a bad idea unless you've got a whole squad for backup. Not to mention rock or steel-types, strong enough psychics, anything with Protect, Quick Guard, Teleport..." Starr rattled the list off without missing a beat. Her own firearm training had always stressed that over and over--if a Pokemon doesn't run away after the first shot, get the fuck out.
"Anyway, point is, if you need to take down a Pokemon, the best offense and defense is just having Pokemon of your own." Humans invented guns to kill each other. And sometimes they didn't want to use a weapon that could think for itself.