You have to pick:

This would be so much fun.

Saddly humans are the domiant species on this planet. So there isn't much that would prove difficult to kill with a bullet or too.

More importantly, what if your profession is killing monsters?

Let's bend the laws of physics. Never could resist a dare! Now you all shall suffer!

i think that monsters would start spawning, and bullets would do damage based on level and quality. if your profession is killing monsters then you win the game.